Month: November 2022

Genetic Links between Traits and Diseases may be Inflated

Genetics
Image source: Pixabay

Many estimates of how strongly traits and diseases share genetic signals may be inflated, according to a new study published in Science that indicates current methods for assessing genetic relationships between traits fail to account for mating patterns.

With genome sequencing technology, scientists have been seeking out the genetic associations between traits and disease risk, hoping to find clues in treating diseases. However, UCLA researchers said their new study cautions against relying too much on genetic correlation estimates. They say that such estimates are confounded by non-biological factors more than has been previously appreciated.

Genetic correlation estimates typically assume that mating is random. But in the real world, partners tend to pair up because of many shared interests and social structures. As a result, some genetic correlations in previous work that have been attributed to shared biology may instead represent incorrect statistical assumptions. For example, previous estimates of genetic overlap between body mass index (BMI) and educational attainment are likely to reflect this type of population structure, induced by “cross-trait assortative mating,” or how individuals of one trait tend to partner with individuals of another trait.

The study authors said genetic correlation estimates deserve more scrutiny, since these estimates been used to predict disease risk, glean for clues for potential therapies, inform diagnostic practices, and shape arguments about human behaviour and societal issues. The authors said some in the scientific community have placed too much emphasis on genetic correlation estimates based on the idea that studying genes, because they are unalterable, can overcome confounding factors.

“If you just look at two traits that are elevated in a group of people, you can’t conclude that they’re there for the same reason,” said lead author Richard Border, a postdoctoral researcher in statistical genetics at UCLA. “But there’s been a kind of assumption that if you can track this back to genes, then you would have the causal story.”

Based on their analysis of two large databases of spousal traits, researchers found that cross-trait assortative mating is strongly associated with genetic correlation estimates and plausibly accounts for a “substantial” portion of genetic correlation estimates.

“Cross-trait assortative mating has affected all of our genomes and caused interesting correlations between DNA you inherit from your mother and DNA you inherit from your father across the whole genome,” said study co-author Noah Zaitlen, professor at UCLA Health.

The researchers also examined genetic correlation estimates of psychiatric disorders, which have sparked debate in the psychiatric community because they appear to show genetic relationships among disorders that seemingly have little similarity, such as attention-deficit hyperactivity disorder and schizophrenia. The researchers found that genetic correlations for a number of unrelated traits could be plausibly attributed to cross-trait assortative mating and imperfect diagnostic practices. On the other hand, their analysis found stronger links for some pairs of traits, like anxiety disorders and major depression, suggesting that there truly is at least some shared biology.

“But even when there is a real signal there, we’re still suggesting that we’re overestimating the extent of that sharing,” Border said.

Source: University of California – Los Angeles Health Sciences

Anti-hyperglycaemic Drugs Raise or Lower MS Risk Depending on Age

Image source: Pixabay CC0

A new study published in the journal Heliyon found that people older than 45 whose Type 2 diabetes (T2D) was treated with anti-hyperglycaemic drugs had an increased risk of multiple sclerosis (MS), especially women, while the reverse was true in under 45s.

“Our findings reinforce the need for a precision medicine approach to preventing MS in these vulnerable populations,” said lead researcher Kathleen Rodgers, PhD, associate director of translational neuroscience at the Center for Innovation in Brain Science.

Multiple sclerosis (MS) is an unpredictable autoimmune neurological disorder that affects the central nervous system and leads to severe physical and cognitive disability. It is estimated that more than 2.8 million worldwide are living with MS.

For people with T2D, growing evidence links metabolic disorders and MS through a common driver of increased autoimmunity. This brings into question the impact of anti-hyperglycaemic therapeutics used to treat T2D, including insulin, on the incidence of MS.

“Previous research has shown a neuroprotective effect of anti-hyperglycaemic medications in Alzheimer’s disease and other related dementias,” Dr Rodgers said. “For MS, we wanted to further examine age and sex differences, particularly among men and women under 45 with Type 2 diabetes.”

They found that men older than 45 years old had a slightly significant increase of MS risk and women older than 45 years exhibited a significant increase in MS incidence after anti-hyperglycaemic exposure. In addition to age differences, the risk analysis by drug class showed that exposure to insulin in patients older than 45 years old was associated with a greater increased risk compared with other therapies.

In patients younger than 45, anti-hyperglycaemic exposure was protective against the development of MS.

The study drew on a US-based insurance claims database of 151 million participants to identify more than 5 million patients with a diagnosis of T2D and either early-onset or late-onset MS. Researchers segmented the data by age – T2D diagnosis before or after age 45 – and sex to decode the factors driving MS risk in both populations, especially in women over 45 years of age.

Source: University of Arizona Health Sciences

Supreme Court of Appeal Reverses Controversial Ivermectin Ruling

Gavel
Photo by Bill Oxford on Unsplash

The Supreme Court of Appeal (SCA) has set aside a controversial supervisory order, granted in April 2021, compelling the South African Health Products Regulatory Authority (SAHPRA) to report back to court every three months on access to ivermectin for use in the treatment of COVID patients.

The court has ruled that there was no evidence to justify the order made by Pretoria High Court Judge Cassim Sardiwalla, that affected parties had not asked for the order, and that they had not been heard before he made it.

The judge had also failed to provide his reasons for making it, the court said.

The issue has its genesis in four applications, one by the African Christian Democratic Party in 2021 against SAHPRA seeking access to ivermectin for the treatment of COVID.

At that time, SAHPRA, which was wary of its use saying there was no reliable research to prove its efficacy, had already put in place its “controlled compassionate use” programme in response to reports of illicit ivermectin-containing products entering the South African market. The programme was stopped in May this year.

In terms of that programme, permission was granted to five importers of unregistered oral solid dosage forms of ivermectin. Health facilities were permitted to hold bulk stock but individual applications were still required. SAPHRA said it would monitor its use.

The ACDP and others approached the court for orders directing SAHPRA to remove restrictions and do “all things necessary to regulate and ensure the manufacture” of ivermectin until such time as clinical evidence demonstrated that it was not effective in the treatment of COVID.

The matter was settled along the same lines as SAHPRA’s programme.

But Judge Sardiwalla, in making the settlement agreement an order of court, also granted a “supervisory order”, putting SAHPRA under his judicial authority in respect of ivermectin.

SAHPRA and the Minister of Health applied for and were granted leave to appeal the order to the SCA.

Read the full judgment here

In heads of argument before the SCA, SAHPRA said its appeal concerned the propriety of the order directing an organ of state to report back to court and be subject to judicial supervision where the dispute had been settled and there was no evidence at all that SAHPRA and the minister would not comply with the settlement agreement.

“It was simply imposed without justification. The order constitutes a grave violation of the Constitution … it violates the rule of law, the right to a fair hearing and the principle of separation of powers,” it argued.

The judge, SAHPRA said, had improperly made findings on matters not in dispute and his written reasons for the supervisory order “do not constitute reasons at all”.

In the SCA ruling, Judge Clive Plaskett said Judge Sardiwalla had suggested to the parties that he “regarded himself as seized of all matters involving ivermectin” and had proposed the supervisory order.

Both SAHPRA and the minister indicated they would oppose this and filed further papers.

While the judge had indicated that he would hear the parties on 6 April 2021, his registrar had informed SAHPRA’s attorney that morning that he had made a decision, he would not hear arguments, and he would send his order to the parties shortly.

No reasons accompanied the order.

SAHPRA and the minister asked for reasons but when these were furnished, they made no mention of the supervisory order or why he granted it.

Judge Plaskett said the first difficulty with the order was that Judge Sardiwalla had not given SAHPRA and the minister a hearing despite knowing that they did not agree to it.

“He agreed to a hearing but inexplicably changed his mind. In these circumstances, an oral hearing was, without doubt, essential.

“Courts decide matters, particularly opposed matters, in open court and the exceptions to this rule are limited.”

Judge Plaskett said the fact that the order had not been applied for by any party required that it be set aside.

He said, further, there was a complete absence of evidence to justify it.

“Important as supervisory orders may be in appropriate cases, the granting of this type of relief must be carefully considered – and justified on the facts – particularly because of its separation of powers implications.

“In this case, not only was there no evidence as to the necessity of a supervisory order but the fact that SAHPRA and the minister had settled the matter and agreed to an order suggests that there was probably no necessity for one.

“Had he allowed the parties to argue the matter, he would have been informed of the separation of powers problem …

“Finally, it strikes me as telling that the reasons he furnished made no mention of the supervisory order – and this despite being pertinently asked to furnish reasons on this very issue,” Judge Plaskett said, upholding the appeal, and setting aside the order.

The ACDP originally opposed SAHPRA’s appeal but shortly before the SCA hearing, it withdrew its opposition on the basis that no cost order would be made against it. The SCA therefore did not order costs.

The ivermectin programme was stopped in May this year.

Republished from GroundUp under a Creative Commons Attribution-NoDerivatives 4.0 International License.

Source: GroundUp

‘Thor’ Actor Takes a Break from Acting after Alzheimer’s Gene Discovery

Actor Chris Hemsworth. Credit: Gage Skidmore / Wikimedia Commons

Actor Chris Hemsworth has announced that he is stepping back from acting in order to focus on preventative measures for Alzheimer’s disease.

The 39-year-old star of ‘Thor’ told Vanity Fair that genetic testing had confirmed that he had two pairs of a gene, APOE4. which is highly predictive of developing Alzheimer’s. About one in four have a single copy while 2–3% carry two copies of the gene.

The reason APOE4 increases Alzheimer’s risk isn’t not well understood. The APOE protein helps carry cholesterol and other types of fat in the bloodstream. Recent studies suggest that problems with brain cells’ ability to process lipids may play a key role in Alzheimer’s and related diseases.

Lipid imbalances can impair many of a cell’s essential processes. This includes creating cell membranes, moving molecules within the cell, and generating energy.

Hemsworth had made the discovery while making the TV series ‘Limitless‘, in which he engages in a variety of activities to push the limits of his own body and mind and explores ways of extending the lifespan.

“My concern was I just didn’t want to manipulate it and overdramatise it, and make it into some sort of hokey grab at empathy, or whatever, for entertainment,” said Hemsworth. “It’s not like I’ve been handed my resignation.”

He emphasises that he is thankful at having made the discovery, as it has made him more appreciative of his life, and it now means he can now take steps to protect his health.

Fortunately, research suggests that there are lifestyle changes that may offer preventative effects for APOE4 carriers, such as reducing stress and getting regular exercise – though the latter is unlikely to be a problem for the already athletic actor. Dietary measures include various low-carbohydrate diets (including ketogenic diets), regular portions of oily fish, cruciferous vegetables and abstaining from alcohol.

Supplements with potential benefits include DHA, quercetin, resveratrol, vitamin D3, vitamin K2, B-vitamin complex and possibly lithium.

Scientists Coax CNS Axons into Regenerating

Source: Pixabay CC0

Severed axons are unable to regenerate, which means that central nervous system (CNS) injuries such as to the spinal cord, can result in permanent loss of sensory and motor function. Presently, there are very limited options to help these patients regain their motor abilities. In mice, researchers have found that deleting a certain gene can cause axons to regrow. The results have recently been published in the scientific journal Neuron.

In a study using mice, a research team led by Associate Professor Kai Liu found that the deletion of PTPN2, a phosphatase-coding gene, in neurons can prompt axons to regrow. Combination with the type II interferon IFNγ, can accelerate the process and increase the number of axons regenerated.

Unlike the CNS, peripheral nerves have a greater ability to regrow and repair by themselves after injury. Scientists have yet to fully understand the relationship between this self-repair and the intrinsic immune mechanism of the nervous system. Thus, the team aimed to resolve how immune-related signalling pathways affected neurons after injury, and whether they could enhance axonal regeneration directly.

This study investigated whether the signalling pathway IFNγ-cGAS-STING had any role in the regeneration process of peripheral nerves. Researchers found that peripheral axons could directly modulate the immune response in their injured environment to promote self-repair after injury.

In previous research, Prof Liu’s team had already demonstrated that elevating the neuronal activity and regulating the neuronal glycerolipid metabolism pathway could  boost axon regenerative capacity. The current study is providing further insights into the search of treatment solutions for challenging conditions such as spinal cord injuries, with one possible option being the joining of several types of different signalling pathways.

Source: EurekAlert!

More Metabolic Imbalances in Paediatric T1D Diagnoses in the Pandemic

Photo by Towfiqu Barbhuiya on Unsplash

During the COVID pandemic, significantly more children and young people had already developed diabetic ketoacidosis when diagnosed with type 1 diabetes (T1D) than in previous years. These findings were reported in The Lancet Diabetes & Endocrinology,

If children and young people have already developed metabolic imbalances (diabetic ketoacidosis) at the time of diagnosis of T1D, this can result in complications such as extended stays in hospital, poorer long-term control of blood sugar levels, brain enema, or even a higher mortality rate.

During the COVID pandemic, diabetes centres around the world saw an increased prevalence of diabetic ketoacidosis in diagnosed cases of T1D. DZD researchers, together with international colleagues, investigated whether the number of diabetic ketoacidosis cases associated with the diagnosis of paediatric T1D increased more than expected. To achieve this, they analysed the number of diabetic ketoacidosis cases before and during the pandemic.

The team evaluated data from 13 national diabetes registers, with 104 290 children and young people aged between 6 months and 18 years old who were diagnosed with T1D between 1 January 2006 and 31 December 2021. The observed prevalence of diabetic ketoacidosis during 2020 and 2021 was compared with predictions based on the years before the pandemic (2006–2019).

Increase greater than expected

Between 2006 and 2019, 23 775 of 87 228 children had diabetic ketoacidosis when diagnosed with T1D (27.3%). The mean annual increase in the prevalence of diabetic ketoacidosis for the entire cohort between 2006 and 2019 was 1.6%. During the pandemic, the numbers were significantly above the predicted prevalence. In 2020, the adjusted observed prevalence of diabetic ketoacidosis was 39.4% (predicted prevalence 32.5%) and 38.9% in 2021 (predicted prevalence 33.0%).

“The increasing prevalence of diabetic ketoacidosis associated with the diagnosis of type 1 diabetes in children is a global problem. There was already an increase in prevalence before the COVID-19 pandemic. During the pandemic, this increase was even greater,” notes DZD scientist Prof. Reinhard W. Holl from Ulm University.

The authors suggest that providing a comprehensive explanation of the classic symptoms of T1D in childhood to the general public, those active in the childcare or daycare settings, and primary care physicians could help raise awareness of the symptoms of T1D. Furthermore, public health measures could be used, eg, implementing a general islet-cell autoantibodies screening program for children to reduce the number of dangerous metabolic imbalances.

Source: Deutsches Zentrum fuer Diabetesforschung DZD

Temporary Low-protein Diet could Enhance Colon Cancer Treatment

Photo by Ella Olsson on Pexels

A brief switch to a low-protein diet could be a key to enhancing colon cancer treatment, say researchers investigating cancer metabolism. They reported their findings in the journal Gastroenterology.

Like all cells, cancer cells need nutrients to survive and grow. One of the most important nutrient sensing molecules in a cell is called mTORC1. Often called a master regulator of cell growth, it lets cells sense different nutrients, thereby growing and proliferating. When nutrients are limited, cells dial down nutrient sensing cascade and turn off mTORC1.

While mTORC1 is known to be hyperactive in colon cancer, the key question is whether colon tumours hijack nutrient sensing pathways to fire up the master regulator.

“In colon cancer, when you decrease the nutrients available in the tumours, the cells don’t know what to do. Without the nutrients to grow, they undergo a kind of crisis, which leads to massive cell death,” said senior author Yatrik M. Shah, PhD, professor at Michigan Medicine.

Researchers found in cells and in mice that a low-protein diet blocked the nutrient signalling pathway that fires up a master regulator of cancer growth.

The regulator, mTORC1, controls how cells use nutritional signals to grow and multiply. It’s highly active in cancers with certain mutations and is known to cause cancer to become resistant to standard treatments. A low-protein diet, and specifically a reduction in two key amino acids, changed the nutritional signals through a complex called GATOR.

GATOR1 and GATOR2 work together to keep mTORC1 in business. When a cell has plenty of nutrients, GATOR2 activates mTORC1. When nutrients are low, GATOR1 deactivates mTORC1. Limiting certain amino acids blocks this nutrient signalling.

Previous efforts to block mTORC have focused on inhibiting its cancer-causing signals. But these inhibitors cause significant side effects — and when patients stop taking it, the cancer comes back. The study suggests that blocking the nutrient pathway by limiting amino acids through a low-protein diet offers an alternative way to shut down mTORC.

“We knew that nutrients were important in mTORC regulation but we didn’t know how they directly signal to mTORC. We discovered the nutrient signalling pathway is just as important to regulate mTORC as the oncogenic signalling pathway,” said study first author Sumeet Solanki, Ph.D., a research investigator at the Rogel Cancer Center.

Researchers confirmed their findings in cells and mice, where they saw that limiting amino acids stopped the cancer from growing and led to increased cell death. They also looked at tissue biopsies from patients with colon cancer, which confirmed high markers of mTORC correlated with more resistance to chemotherapy and worse outcomes. Solanki said this could provide an opportunity to direct treatment for patients with this marker.

“A low-protein diet won’t be standalone treatment. It has to be combined with something else, such as chemotherapy,” Solanki said.

The risk with a low-protein diet is that people with cancer often experience muscle weakness and weight loss, which limiting protein could exacerbate.

“Putting cancer patients on a protein-deficient diet long-term is not ideal. But if you can find key windows – like at the start of chemotherapy or radiation – when patients could go on a low protein diet for a week or two, we could potentially increase the efficacy of those treatments,” Shah said.

Further research will refine this concept of a therapeutic window to limit amino acids. Researchers will also seek to understand how these pathways are creating resistance to treatment and whether an inhibitor could block the GATOR complexes.

Source: Michigan Medicine – University of Michigan

Metastases Survive by Adapting to Different Tissues

Source: National Cancer Institute on Unsplash

In a breakthrough for understanding metastases, researchers have found that, as metastatic cancers spread to different parts of the body, they adapt their metabolism to the tissue in which they grow. The findings, which help further break down the puzzle of metastasis, are published in PNAS.

Metabolism in the body is an important target for cancer treatments, where the focus is on stopping the progress of cancer cells.

“Obviously, the local environment affects the cancer cells more than previously known. The metastatic tumours should show the same metabolic properties no matter where in the body they are located, but we discovered that the cancer cells largely adapted their metabolism to the new tissue in order to continue to develop and grow. This is important knowledge, which shows that we cannot consider the metastases as their original tumours,” says Fariba Roshanzamir, PhD in Systems and Synthetic Biology at Chalmers and the study’s lead author.

Cutting off cancer metabolism

Fariba Roshanzamir works in Professor Jens Nielsen’s research group at Chalmers and has, together with Swedish and international colleagues, been able to establish the groundbreaking results. The study focused primarily on triple-negative breast cancer but the conclusions can, according to the researchers, be applied to all types of metastatic cancer. This opens new doors to develop more effective treatments.

“If we manage to shut down the metabolism in a tumour, it will stop working and this study provides important keys to better understand what to target. Selecting metabolic inhibitors that specifically target the metastases in the organs to which the tumour has spread, rather than treating them as their original tumours, is of great importance to be able to find good strategies for treatments in the future,” she says.

Source: Chalmers University of Technology

Alzheimer’s Prions also Appear in Down Syndrome

Plaques and neurons. Source: NIAH

The brains of people with Down syndrome develop the same neurodegenerative tangles and plaques associated with Alzheimer’s disease and they frequently demonstrate signs of the neurodegenerative disorder in their 40s or 50s. A new study in the journal PNAS shows that these tangles and plaques are driven by the same amyloid beta (Aß) and tau prions that they showed are behind Alzheimer’s disease.

Prions begin as normal proteins that become misshapen and self-propagate. They spread through tissue like an infection by forcing normal proteins to adopt the same misfolded shape. In both Alzheimer’s and Down syndrome, as Aß and tau prions accumulate in the brain, they cause neurological dysfunction that often manifests as dementia.

Tau tangles and Aß plaques are evident in most people with Down syndrome by age 40, according to the National Institute on Aging, with at least 50% of this population developing Alzheimer’s as they age.

The new study highlights how a better understanding of Down syndrome can lead to new insights about Alzheimer’s, as well.

“Here you have two diseases – Down syndrome and Alzheimer’s disease – that have entirely different causes, and yet we see the same disease biology. It’s really surprising,” said Stanley Prusiner, MD, the study’s senior author, who was awarded the Nobel Prize in 1997 for his discovery of prions.

Down syndrome is the most common neurodegenerative disease among younger people in the United States, while Alzheimer’s is the most common among adults.

Down syndrome occurs because of an extra copy of chromosome 21. Among the many genes on that chromosome is one called APP, which codes for one of the major components of amyloid beta. With an extra copy of the gene, people with Down syndrome produce excess APP, which may explain why they develop amyloid plaques early in life.

A clearer picture in young brain

It’s been known for some time that Aß plaques and tau tangles are present in both Down syndrome and Alzheimer’s. Having shown earlier that these neurodegenerative features are provoked by prions in Alzheimer’s, the researchers wanted to know whether the same aberrant proteins were present in the brains of people with Down syndrome.

While these plaques and tangles in the brains of people with Alzheimer’s disease have been well-studied, it can be challenging to discern which changes in the brain are from old age and which are from prion activity, said Prusiner.

“Because we see the same plaques-and-tangles pathology at a much younger age in people with Down syndrome, studying their brains allows us to get a better picture of the early process of disease formation, before the brain has become complicated by all the changes that go on during aging,” he said. “And ideally, you want therapies that address these early stages.”

Employing a variation on the novel assay they used in the Alzheimer’s study, the team looked at donated tissue samples from deceased people with Down syndrome, which they obtained from biobanks around the world. Of the 28 samples from donors aged 19 to 65 years old, the researchers were able to isolate measurable amounts of both Aß and tau prions in almost all of them.

New insights could yield preventative measures

The results confirm not only that prions are involved in the neurodegeneration seen in Down syndrome, but that Aß drives the formation of tau tangles as well as amyloid plaques, a relationship that has been suspected but not proven.

“The field has long tried to understand what the intersection is between these two pathologies,” said lead author Carlo Condello, PhD, also a member of the UCSF Institute for Neurodegenerative Diseases. “The Down syndrome case corroborates the idea; now you have this extra chromosome that’s driving the Aß, and there’s no tau gene on the chromosome. So, it’s truly by increasing the expression of Aß that you kick off production of the tau.”

These and other insights gained from studying the brains of people with Down syndrome will lead to a much better picture of how prions begin to form in the first place, said Condello.

Whether the Down syndrome brain tissue will prove to be the ultimate model for developing treatments for Alzheimer’s remains to be seen, the researchers said. While the two disorders share many similarities in their prion pathobiology, there are some differences that may be limiting.

Still, the researchers said, studying the plaques and tangles in Down syndrome is a promising route to identifying the specific prions that arise at the very earliest stages of the disease process. That insight could open new vistas on not only treating but perhaps even fending off Alzheimer’s disease.

“If we can understand how this neurodegeneration begins, we are one big step closer to being able to intervene at a meaningful point and actually prevent these large brain lesions from forming,” Condello said.

Source: University of California – San Francisco

ADHD Drug for Amphetamine Addiction Linked to Reduced Risks

Photo by Towfiqu barbhuiya on Unsplash

In a large registry-based study investigating medication use in people with substance use disorders, the ADHD medication lisdexamfetamine was associated with the lowest risk of hospitalisation and death in people with amphetamine addiction. The findings, which also showed drugs which worsened outcomes, were published in JAMA Psychiatry.

“Our results suggest that lisdexamfetamine is associated with the best outcomes, and encourage the conduction of randomised controlled trials to explore this further, says first author Jari Tiihonen, professor at Karolinska Institutet.

Worldwide, amphetamines are the second most used illicit drugs and hospitalisations related to its use are rising.

At present, there are no approved pharmacological interventions available for treating amphetamine or methamphetamine addiction. While certain medications have shown promising results, the studies so far have often been small and convincing evidence is lacking.

Registry-based study

In the present study, the researchers investigated the association between generally used medications among persons with substance use disorder and the risk of two primary outcomes in people with amphetamine or methamphetamine use disorder: 1) hospitalisation due to substance use disorder or 2) hospitalisation due to any cause, or death.

The study enrolled nearly 14 000 individuals aged 16 to 64 years in Sweden with a registered first-time diagnosis of amphetamine or methamphetamine use disorder from July 2006 to December 2018. Individuals with schizophrenia or bipolar disorder were excluded.

Patients were followed from diagnosis until they died, emigrated, were diagnosed with schizophrenia or bipolar disorder or the study ended. The median follow-up time was 3.9 years.

Comparing effects in the same individual

The researchers looked at how the risk of hospitalisation or death for each individual differed depending on whether they were on or off the medication at that time.

”Our results show that lisdexamfetamine, a medication approved for treating ADHD and in some countries also for binge eating, was the only specific medication associated with reduced risk of hospitalisation and death,” says first author Milja Heikkinen, researcher at the University of Eastern Finland and Niuvanniemi Hospital.

The risk of hospitalisation due to substance use disorder was 18% lower and the risk of hospitalisation due to any cause or death was 14% lower during periods of lisdexamfetamine use, compared to periods without the ADHD medication.

The combination of two or more different medications for substance use disorder was also associated with a lower risk of hospitalisation or death.

Some medications linked to worse outcomes

Use of benzodiazepines was associated with poorer outcomes; 17% higher risk of hospitalisation due to substance use disorder and 20% higher risk of hospitalisation due to any cause or death, during periods of use compared to periods of non-use. The use of antidepressants was also associated with slightly worse outcomes than non-use.

The researchers note that pharmacological treatments are often discontinued when the clinical state has improved, and are started when the clinical state deteriorates. Therefore, the results may underestimate the putative beneficial effect of treatments. To control for this phenomenon, the researchers conducted analyses by omitting the first 30 days of use. The results were then in line with the main analyses.

Source: Karolinska Institutet