Common Diabetes Drug Linked to 30% Higher Chance of Living Past 90

Women with type 2 diabetes who take metformin may have a significantly better chance of living into their 90s compared to those using other diabetes medications, according to new research from UC San Diego. This large-scale study suggests the widely prescribed diabetes drug might play a role in promoting exceptional longevity, adding to growing evidence that metformin could influence fundamental aging processes.

The study, published May 19 in the Journal of Gerontology: Medical Sciences, found that women taking metformin had a 30% lower risk of death before age 90 compared to those taking sulfonylurea, another common class of diabetes medication. These findings emerge from data gathered through the Women’s Health Initiative (WHI), one of the nation’s most comprehensive and long-running studies of women’s health, with over three decades of follow-up information.

Could a medication already in millions of medicine cabinets hold the key to extending human lifespan? While the researchers caution against drawing definitive conclusions, the results add intriguing evidence to metformin’s potential role beyond diabetes control.

Metformin as a Possible “Gerotherapeutic”

Metformin has increasingly attracted attention from longevity researchers as a potential “gerotherapeutic” – a medication that might slow aging processes. Originally approved for diabetes management, the drug works primarily by reducing glucose production in the liver and improving insulin sensitivity.

What makes this study noteworthy is its focus on exceptional longevity, specifically defined as living to age 90 or beyond. Rather than looking only at general mortality risk, researchers examined whether metformin use was associated with reaching this advanced age milestone.

The research team employed a rigorous methodology called “target trial emulation,” which aims to replicate the conditions of a randomized controlled trial using observational data. They carefully matched participants based on numerous factors including demographics, lifestyle behaviors, diabetes duration, and other health conditions.

Key Findings About Metformin and Longevity

• Women taking metformin had a 30% lower risk of death before age 90 compared to those taking sulfonylurea
• The incidence rate of death before age 90 was 3.7 per 100 person-years in the metformin group versus 5.0 in the sulfonylurea group
• Researchers carefully matched 438 women with type 2 diabetes based on numerous health and demographic factors
• The study included only women who were at least 60 years old when beginning either medication
• This represents the first study specifically examining metformin’s association with exceptional longevity

Data from a Landmark Women’s Health Study

The findings come from analysis of the Women’s Health Initiative, a massive research project that has been tracking the health of American women since the 1990s. The WHI has made enormous contributions to our understanding of women’s health, generating over 2,400 scientific publications and influencing countless health recommendations.

Originally enrolling 161,808 women aged 50-79 in the mid-1990s, the study continues to follow over 42,000 participants who are now 78-108 years old. This extraordinary long-term data collection has created a unique resource for studying aging-related health outcomes.

The study recently received renewed funding from the National Institutes of Health, ensuring continued research into factors affecting women’s health and longevity.

Limitations and Future Research Needs

While these results are promising, the researchers emphasize important limitations. Since metformin wasn’t compared to a placebo in a randomized controlled trial, they cannot definitively establish that metformin directly causes increased longevity.

The study notes that “because this comparison was not made to placebo in an RCT and given the observational design with potential for residual confounding, causality cannot be inferred.” In other words, despite the researchers’ best efforts to account for other variables, unidentified factors might influence both medication choice and survival.

Led by Associate Professor Aladdin H. Shadyab and Distinguished Professor Andrea LaCroix at UC San Diego’s Herbert Wertheim School of Public Health and Human Longevity Science and School of Medicine, the research team suggests these findings contribute to the growing understanding of metformin’s potential role in promoting human health and longevity.

Broader Implications for Aging Research

The results align with the increasing scientific interest in repurposing existing medications like metformin for their potential anti-aging effects. Several mechanisms have been proposed for how metformin might influence aging, including reducing inflammation, improving cellular energy metabolism, and modifying gut microbiome composition.

Other research has suggested metformin may reduce the risk of certain age-related diseases such as cancer and cognitive decline, even in people without diabetes. The drug is currently being investigated in clinical trials specifically designed to test its anti-aging properties.

These findings about exceptional longevity add an important piece to the puzzle of how medications might influence not just lifespan but also “healthspan” – the portion of life spent in good health. As our population ages, such research becomes increasingly relevant for developing strategies to extend healthy aging and reduce the burden of age-related diseases.

For the millions of people already taking metformin for diabetes management, these results provide an intriguing suggestion that their medication might offer benefits beyond blood sugar control. However, experts caution that people should not take metformin solely for anti-aging purposes without medical supervision, as more definitive evidence is still needed.