History of Cannabis Smoking Linked to Memory Complaints in Older Women | Research

The takeaway

Among 15,378 women over 65, those who had ever smoked cannabis were 27-30% more likely to report cognitive complaints, with regular past smokers at 61% higher risk than never-users.

Older adults with a history of cannabis use, geriatric medicine professionals, and anyone concerned about long-term cognitive effects of cannabis.

What the researchers found

Ever smoking cannabis was associated with increased odds of subjective cognitive complaints across three follow-ups: OR 1.27 (2nd), 1.28 (3rd), 1.30 (4th). Regular smokers had stronger associations than occasional smokers (OR 1.61 vs. 1.19 at 2nd follow-up). Results were consistent across subgroup and sensitivity analyses.

Why it matters

As the first generation of widespread cannabis users enters older age, understanding long-term cognitive effects becomes critical. This large prospective study suggests a dose-dependent association between cannabis history and later cognitive complaints.

The numbers in context

15,378 women. 25.8% (3,973) ever smoked cannabis. Most use occurred in early adulthood. OR for ever-smokers: 1.27-1.30 across follow-ups. Regular smokers: OR 1.61. Occasional smokers: OR 1.19. Assessed at 2nd (2011-14), 3rd (2014-16), and 4th (2017-19) follow-ups.

How the study worked

Prospective cohort analysis of 15,378 women aged 65+ from the NIH Sister Study. Cannabis smoking history reported at enrollment (2003-2009). Cognitive complaints assessed via AD8 screener at three follow-ups (2011-2019). Multivariable joint models with adjustment for confounders.

What this study cannot tell us

Subjective cognitive complaints are not the same as dementia diagnosis. Cannabis use was recalled decades later (recall bias). Cannot separate cannabis effects from associated lifestyle factors. Mostly white sample. No information on cannabis use after enrollment.

How to read the evidence

Large prospective cohort with repeated measurements and appropriate covariate adjustment — methodologically strong for observational research.

When this study was published

Published in 2026, providing important long-term follow-up data as the first generation of widespread cannabis users ages.

The bigger picture

Baby boomers were the first generation with widespread cannabis use, and they're now reaching ages where cognitive decline becomes a concern. This study suggests that earlier cannabis use may contribute to cognitive vulnerability decades later, though the effect sizes are modest.

Questions still open

Would objective cognitive testing confirm these subjective findings? Is the risk specifically from smoking (combustion) or cannabis itself? Do current older adults who use cannabis face different risks?

Common questions

Can past cannabis use affect memory in old age?

This study of over 15,000 women found those who smoked cannabis earlier in life were 27-30% more likely to report memory and thinking complaints after age 65. Regular smokers had 61% higher odds, suggesting a dose-dependent relationship.

Should past cannabis users worry about dementia?

The study measured subjective complaints, not dementia diagnoses. The increased risk was modest (27-30%), and many other factors affect cognitive aging. However, regular past use showed stronger associations, suggesting it's worth monitoring cognitive health.

Read the original research

History of Cannabis Smoking and Subjective Cognitive Complaints in Older Women.

Neuroepidemiology, 1-11

View on PubMed ↗Publisher’s paper ↗

Citation

Ding, Guoyong; Bohnert, Kipling M; Li, Chenxi; Plassman, Brenda L; Liang, Xiaoyu; Yuan, Yaqun; D'Aloisio, Aimee A; White, Alexandra J; Sandler, Dale P; Chen, Honglei. (2026). History of Cannabis Smoking and Subjective Cognitive Complaints in Older Women.. Neuroepidemiology, 1-11. https://doi.org/10.1159/000550276