英国埃克塞特大学医学院、牛津大学等研究人员的最新研究揭示了生活方式和遗传风险与痴呆症发病率的关系。这一成果于2019年8月6日发表在国际学术期刊《美国医学会杂志》上。

在这项包括196383人的回顾性队列研究中，参与者均为欧洲人，年龄至少60岁，没有认知障碍或痴呆，他们在2006至2010年间参与研究，并随访至2016-2017年。健康的生活方式包括不抽烟、定期体育活动、健康饮食和适度饮酒，研究机构对所有参与者的痴呆风险进行评分。

结果显示，高遗传风险和不良生活方式参与者的得分与低遗传风险和良好生活方式参与者相比，发生痴呆症的风险比为2.83，具有统计学意义。良好的生活方式与较低的痴呆症风险相关，而遗传风险与健康的生活方式之间没有显著的交互作用。 在没有认知障碍或痴呆的老年人中，不良的生活方式和高遗传风险都与较高的痴呆风险显著相关。而在高遗传风险的参与者中，良好的生活方式也与较低的痴呆症风险相关。

研究人员表示，不管遗传风险如何，健康的生活方式可降低患痴呆症的风险，但生活方式因素能在多大程度上抵消这种风险，目前尚不清楚。

附：英文原文

Title: Association of Lifestyle and Genetic Risk With Incidence of Dementia

Author: Ilianna Lourida, Eilis Hannon,Thomas J. Littlejohns,Kenneth M. Langa,Elina Hyppönen, El?bieta Ku?ma,David J. Llewellyn

Issue&Volume: Vol 322, No.5

Abstract:

Importance  Genetic factors increase risk of dementia, but the extent to which this can be offset by lifestyle factors is unknown.

Objective  To investigate whether a healthy lifestyle is associated with lower risk of dementia regardless of genetic risk.

Design, Setting, and Participants  A retrospective cohort study that included adults of European ancestry aged at least 60 years without cognitive impairment or dementia at baseline. Participants joined the UK Biobank study from 2006 to 2010 and were followed up until 2016 or 2017.

Exposures  A polygenic risk score for dementia with low (lowest quintile), intermediate (quintiles 2 to 4), and high (highest quintile) risk categories and a weighted healthy lifestyle score, including no current smoking, regular physical activity, healthy diet, and moderate alcohol consumption, categorized into favorable, intermediate, and unfavorable lifestyles.

Main Outcomes and Measures  Incident all-cause dementia, ascertained through hospital inpatient and death records.

Results  A total of 196?383 individuals (mean [SD] age, 64.1 [2.9] years; 52.7% were women) were followed up for 1?545?433 person-years (median [interquartile range] follow-up, 8.0 [7.4-8.6] years). Overall, 68.1% of participants followed a favorable lifestyle, 23.6% followed an intermediate lifestyle, and 8.2% followed an unfavorable lifestyle. Twenty percent had high polygenic risk scores, 60% had intermediate risk scores, and 20% had low risk scores. Of the participants with high genetic risk, 1.23% (95% CI, 1.13%-1.35%) developed dementia compared with 0.63% (95% CI, 0.56%-0.71%) of the participants with low genetic risk (adjusted hazard ratio, 1.91 [95% CI, 1.64-2.23]). Of the participants with a high genetic risk and unfavorable lifestyle, 1.78% (95% CI, 1.38%-2.28%) developed dementia compared with 0.56% (95% CI, 0.48%-0.66%) of participants with low genetic risk and favorable lifestyle (hazard ratio, 2.83 [95% CI, 2.09-3.83]). There was no significant interaction between genetic risk and lifestyle factors (P = .99). Among participants with high genetic risk, 1.13% (95% CI, 1.01%-1.26%) of those with a favorable lifestyle developed dementia compared with 1.78% (95% CI, 1.38%-2.28%) with an unfavorable lifestyle (hazard ratio, 0.68 [95% CI, 0.51-0.90]).

Conclusions and Relevance  Among older adults without cognitive impairment or dementia, both an unfavorable lifestyle and high genetic risk were significantly associated with higher dementia risk. A favorable lifestyle was associated with a lower dementia risk among participants with high genetic risk.

DOI: 10.1001/jama.2019.9879

Source: https://jamanetwork.com/journals/jama/article-abstract/2738355