The Contribution of Diseases to the Male-Female Disability-Survival Paradox in the Very Old: Results from the Newcastle 85+ Study Andrew Kingston 1 *, Karen Davies 1 , Joanna Collerton 1 , Louise Robinson 2 , Rachel Duncan 2 , John Bond 2 , Thomas B. L. Kirkwood 1 , Carol Jagger 1 1 Institute for Ageing and Health, Newcastle University, Newcastle upon Tyne, United Kingdom, 2 Institute for Health and Society, Newcastle University, Newcastle upon Tyne, United Kingdom Abstract Background: Explanations for the male-female disability-survival paradox - that woman live longer than men but with more disability - include sex differences in diseases and their impact on disability and death. Less is known about the paradox in the very old. We examine sex differences in the presence and impact of disabling and fatal diseases accounting for the male- female disability-survival paradox in very late life. Methods: We use data from the Newcastle 85+ Study, a cohort of people born in 1921 and all recruited at age 85 in 2006. Participants underwent a health assessment (HA) at baseline, 18 months, 36 months, 60 months, and a review of their GP records (GPRR) at baseline and 36 months. We used multi-state modelling to assess the impact of specific diseases on disability and death. Disability (measured via ADLs/IADLs) was categorised as no disability (difficulty with 0 activities), or disabled (difficulty with one or more activities). Diseases were ascertained from review of general practice records and cognitive impairment which was defined as an sMMSE of 21 or less (from health assessment). Results: In participants who had complete HA and GPRR, women had more arthritis (RR = 1.2, 95% CI: 1.1–1.3) and hypertension (RR = 1.2, 95%CI 1.0–1.3), more disability, and were more likely disabled at all follow-ups. From multistate models, women with cerebrovascular disease (HR: 2.6, 95% CI: 2.1–3.4) or respiratory disease (HR: 2.0, 95% CI: 1.4–3.0) were more likely to become disabled than those without but this did not hold for men (sex difference p,0.01). Men were more likely to die from respiratory disease (HR: 2.2, 95% CI: 1.8–2.8) but this did not hold for women (p = 0.002). Conclusion: The disability-survival paradox was still evident at age 85 and appears due to sex differences in the types of diseases and their impact on the disability pathway. Citation: Kingston A, Davies K, Collerton J, Robinson L, Duncan R, et al. (2014) The Contribution of Diseases to the Male-Female Disability-Survival Paradox in the Very Old: Results from the Newcastle 85+ Study. PLoS ONE 9(2): e88016. doi:10.1371/journal.pone.0088016 Editor: Antony Bayer, Cardiff University, United Kingdom Received October 2, 2013; Accepted January 2, 2014; Published February 7, 2014 Copyright: ß 2014 Kingston et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Funding: The Newcastle 85+ Study was supported by a combined grant from the Medical Research Council and Biotechnology and Biological Sciences Research Council (reference G0500997), and a grant from the Newcastle Healthcare Charity and the Dunhill Medical Trust. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Competing Interests: The authors have declared that no competing interests exist. * E-mail: andrew.kingston@ncl.ac.uk Introduction Women live longer than men on average, but their longer life expectancy is accompanied by more years with disability, both in absolute terms and as a proportion of remaining life [1]. Understanding the basis of this ‘‘disability-survival paradox’’ [2,3] is important for addressing the different health challenges faced by very old men and women, the fastest growing age group in many countries [4], and could inform more effective clinical practice. The paradox may derive from intrinsic differences (biological, social or behavioural) between men and women [3,5,6]. Women are reported to have a greater number of acute and non-fatal chronic diseases, whereas men have fewer diseases in total but more of these are life-threatening [5,7,8]. A potential basis for a biological difference between men and women is the actions of sex hormones. Female sex hormones bring benefits for women by modulating lipid levels, and hence cardiovascular risk, and by affecting the immune response [5]. A recent report describes longer lifespans for Korean eunuchs than intact men, which is consistent with the idea that male sex hormones, notably testosterone, may be a risk factor for earlier mortality [9], notwithstanding the limitations of such historical studies. Behav- ioural differences between women and men include their perception of symptoms and readiness to consult with healthcare professionals. Sex differences in physician diagnostic patterns and self-reporting of disease may also contribute [10]. It is also possible that the progression of disease to disability may be more marked for women than men, especially if women are under-treated for some conditions [11]. Men’s higher mortality may also result from a greater severity of disease, which is inadequately captured in analyses based on the simple presence/absence of a condition. The PLOS ONE | www.plosone.org 1 February 2014 | Volume 9 | Issue 2 | e88016