Marriage and risk of dementia: systematic review and meta-analysis of observational studies

This  JNNP meta-analysis, which included 15 studies with 812 047 participants, showed an elevated dementia risk in lifelong single (42%) and widowed (20%) but not divorced persons compared with those who were married.1 Although one study from Sweden contributed the vast majority (92%) of participants, the other studies were also broadly in agreement and, importantly, came from a wide range of countries across the world: Europe (France, Germany, Italy, Sweden), North and South America (Brazil, USA) and Asia (China, Japan, South Korea, Taiwan). Furthermore, the robustness of the association was shown by sensitivity analyses for demographic factors (sex, whether study subjects were born before or after 1927) and study methodology (type, quality). However, the association with dementia subtypes was not significant likely …