Mortality in single fathers compared with single mothers and partnered parents: a population-based cohort study

Background — Single parent families, including families headed by single fathers, are becoming increasingly common around the world. Previous evidence suggests that single parenthood is associated with adverse health outcomes and increased mortality; however, most studies have focused on single mothers, with little known about the health of single fathers. This study aimed to examine mortality in a large population-based sample of Canadian single fathers compared with single mothers and partnered fathers and mothers.

Methods — We used a representative sample of 871 single fathers, 4590 single mothers, 16 341 partnered fathers, and 18 688 partnered mothers from the Canadian Community Health Survey (cycles 2001–12; earliest survey date: Sept 5, 2000; latest survey date: Dec 24, 2012). We anonymously linked survey participants to health administrative database records to ascertain health status at baseline and mortality from survey date up to Oct 28, 2016. We included individuals who were aged 15 years or older, living in a household with one or more biological or adopted child younger than 25 years, and living in Ontario, and we excluded those who left Ontario during the study period or had data discrepancies. Single parents were defined as those who were divorced, separated, widowed, or single, never married,and non-cohabitating, and partnered parents were defined as those who were married or common-law partners. We investigated differences in mortality using Cox proportional hazards models with adjustment for sociodemographic, lifestyle, and clinical factors.

Findings — Median follow-up was 11.10 years (IQR 7.36–13.54). Mortality in single fathers (5.8 per 1000 person-years) was three-times higher than rates in single mothers (1.74 per 1000 person-years) and partnered fathers (1.94 per 1000 person-years). Single fathers had a significantly higher adjusted risk of dying than both single mothers (hazard ratio [HR] 2.49, 95% CI 1.20–5.15; p=0.01) and partnered fathers (2.06, 1.11–3.83; p=0.02).

Interpretation — In this first head-to-head comparison of mortality across single and partnered parent groups, we found that single fathers had the least favourable risk factor profile and greatest risk of mortality. Social histories might help physicians identify these high-risk patients. Further work is needed to understand the causes of this high mortality risk and how clinical and public health interventions improve lifestyle and behavioural risk factors.