Living alone increases the risk of developing type 2 diabetes mellitus: A systematic review and meta-analysis based on longitudinal studies.

BACKGROUND: Living alone is a prevalent psychological issue that has been found to have significant implications for lifestyle and health status. While considerable research has been conducted to explore the relationship between living alone and the risk of developing type 2 diabetes mellitus (T2DM), the majority of studies have been cross-sectional, leaving direct correlations elusive. Therefore, this study aims to analyze data from longitudinal studies to determine whether living alone increases the risk of T2DM.

METHODS: A comprehensive search was conducted in the PubMed, Cochrane, and Embase databases to identify studies examining the association between living alone and T2DM risk. The search encompassed studies published until September 2023. Pooled analysis utilized the random-effects model with inverse variance and included adjusted hazard ratios (HRs) and their corresponding 95% confidence intervals (CIs).

RESULTS: The meta-analysis comprised a total of 8 studies, which consisted of 5 prospective cohort studies and 3 retrospective cohort studies. The total population under consideration included 11,686,677 individuals without T2DM, of whom 54.3% were female. Among this population, 396,368 individuals developed T2DM. To account for heterogeneity, a random-effects model was employed. Overall, the pooled data demonstrated a significant association between living alone and an increased risk of T2DM when compared to living with others (HR 1.24, 95% CI 1.06-1.46). Subgroup analysis revealed that this risk was not statistically significant for either males (HR 1.28, 95% CI 0.93-1.76) or females (HR 1.06, 95% CI 0.84-1.33), nor in prospective cohort studies (HR 1.26, 95% CI 0.91-1.74) or retrospective cohort studies (HR 1.26, 95% CI 0.91-1.74).

CONCLUSION: Individuals living alone faced a significantly higher risk of developing diabetes compared to those who did not live alone. However, no significant difference in this risk was observed between genders and study types. Further high-quality studies are necessary in the future to elucidate this causal association.