飲食品質、睡眠、心血管健康及生物老化之關聯研究

Abstract

背景：飲食品質和睡眠等可調整之生活型態因子，對促進心血管健康及延緩老化扮演著重要角色。然而，植物性飲食對心血管健康及睡眠的影響在亞洲族群中未有一致性證據，飲食品質與睡眠交互影響心血管健康及生物老化之關聯亦尚未釐清。同時，台灣仍缺乏一套簡便、有效的飲食品質評估工具來進行臨床評估及介入。

目的：本博士論文旨在探討飲食品質、睡眠、心血管健康與生物老化之間的交互關聯，研究目的包含：（1）探討植物性飲食與失眠風險之前瞻性關聯；（2）總述植物性飲食與心血管疾病的關聯性之現有證據；（3）研發並驗證快速飲食品質評估工具rapid Prime Diet Quality Score（rPDQS）；（4）評估飲食品質與睡眠對心血管健康與生物年齡之影響。

方法：本論文包含四項研究，第一項研究研究使用慈濟健康研究（TCHS）中無失眠病史之參與者（2007-2009），並追蹤至2018年，藉由全民健保資料庫（NHIRD）連結確認失眠新發個案，並以Cox比例風險模型分析植物性飲食（素食身分及健康植物性飲食指數hPDI得分）與失眠風險之關聯。第二項為系統性回顧及統合分析，採用隨機效應模型與劑量反應分析，整合植物性飲食與心血管疾病發生率相關的前瞻世代研究。第三項研究將rPDQS中文化並於TCHS和聯安健康研究（LHS）中驗證其效度，透過食物頻率問卷（FFQ）衍生之飲食攝取、營養素及其他飲食品質指標AHEI-2010等），進行相關性與分類一致性分析。第四項研究使用LHS的橫斷面數據，透過多元線性回歸分析飲食品質、睡眠時數、睡眠品質與心血管健康（依據Life’s Essential 8指標）與生物老化（PhenoAgeAccel）之關聯，再利用中介分析，以檢驗睡眠是否中介飲食品質與健康結果之關係。

結果：四項研究結果顯示：第一，TCHS資料顯示，55,562人年追蹤期間發現464例失眠個案，男性（HR 0.47）與女性（HR 0.71）的素食者失眠風險顯著較低。具hPDI最高五分位之男性風險亦顯著下降（HR 0.50）。第二，統合分析發現高植物性飲食與心血管疾病（RR 0.84）及冠心病風險（RR 0.89）風險下降具顯著關聯，但與中風風險的關聯未能確定。劑量反應分析顯示，較高的植物性飲食指數（PDI）和健康植物性飲食指數（hPDI）分數與較低的心血管疾病風險相關。第三，rPDQS總分與AHEI-2010得分相關性良好（r=0.66與0.60），並與多種營養素顯著關聯，顯示具有良好的相對效度。第四，LHS分析顯示高飲食品質者之CVH（log）分數較佳，且PhenoAgeAccel較低，顯示老化延緩。年齡與性別具顯著交互作用，惟未觀察到睡眠具中介效果。

結論：綜合四項研究結果，本論文提供實證支持植物性飲食與足夠睡眠有助於促進心血管健康並延緩生物老化。rPDQS為一項實用且有效的飲食品質篩檢工具，適用於健康檢查與預防保健，對於提升台灣族群之健康壽命具重要意涵。

Background: Diet quality and sleep are modifiable lifestyle factors known for their roles in cardiometabolic health and healthy aging. However, evidence regarding the impact of plant-based diets on cardiovascular health (CVH) and sleep, particularly among Asian populations, is inconsistent. Additionally, the relationship between diet, sleep, CVH, and biological aging is not well understood. Moreover, there is a need for practical diet quality assessment tools to evaluate dietary patterns, guide interventions, and monitor changes in Taiwan.

Aims: This doctoral dissertation explored the interrelationships among diet quality, sleep, cardiovascular health, and biological aging. Specifically, the objectives were to: (1) examine the association between plant-based dietary patterns and insomnia risk in a Taiwanese cohort; (2) systematically review and quantify the association between plant-based dietary patterns and cardiovascular disease risk through a meta-analysis; (3) develop and validate the rapid Prime Diet Quality Score (rPDQS) as an brief dietary assessment tool within Taiwanese populations; and (4) investigate the associations of diet quality and sleep characteristics on cardiovascular health (using Life’s Essential 8 metrics) and biological aging (via PhenoAgeAccel).

Methods: The dissertation consists of four studies. First, participants without insomnia were recruited from the Tzu Chi Health Study (TCHS) between 2007 and 2009 and followed until 2018. Incident cases of insomnia were identified by linkage with the National Health Insurance Research Database (NHIRD). Associations between plant-based diets (vegetarian status and adherence to the healthful plant-based index [hPDI]) and insomnia were estimated using Cox proportional hazard models. Second, a systematic review and meta-analysis were conducted using random effects models and dose-response analyses to synthesize prospective observational studies examining the associations between plant-based diets and cardiovascular disease (CVD) incidence among adults. Third, the rapid Prime Diet Quality Score (rPDQS) screener was adapted to Chinese and validated against food-frequency questionnaire-derived food groups, nutrients, and existing diet quality indices in two study populations – TCHS and the Lianan Health Study (LHS). Finally, using data obtained from LHS, the relationships between diet quality, sleep, cardiovascular health (CVH), and biological aging were examined using multivariable linear regression models. Mediation analyses were performed to determine whether sleep mediates the relationship between diet and health outcomes.

Results: First, 464 incident cases of insomnia were identified in the 55,562 person-years of follow-up from the study examining the relationship between plant-based diets and insomnia risk. Insomnia risk was lower in vegetarians compared to non-vegetarians for males (HR 0.47; 95% CI 0.27-0.81) and females (HR 0.71; 95% CI 0.55-0.91). Male participants with the highest healthful Plant-based Diet Index (hPDI) had a significantly lower risk of insomnia (HR 0.50; 95% CI 0.30-0.85) compared to those in the lowest quintile. Second, the systematic review and meta-analysis included 16 articles describing 13 cohorts. The highest adherence to a plant-based diet is associated with a lower risk of cardiovascular disease (CVD) (RR 0.84; 95% CI 0.79-0.90) and coronary heart disease (RR 0.89; 95% CI 0.81-0.97), but not stroke. Dose-response meta-analyses showed that higher overall plant-based diet index (PDI) and healthful PDI (hPDI) scores were associated with reduced CVD risk. Third, total rPDQS scores demonstrated strong significant correlations with AHEI-2010 scores in both TCHS (N = 5460) and LHS (N = 101) study populations (r=0.66 and 0.60, respectively), showing acceptable to good validity. Total rPDQS scores were positively associated with health-promoting dietary components such as dietary fiber, magnesium, iron, niacin, and folate, while inversely correlating with saturated fat, cholesterol, and carbohydrates. Finally, in the LHS population (N = 593), multivariable regression analyses indicated that diet quality (via rPDQS scores) and sleep duration were linked to favorable cardiovascular health (CVH) scores and lower biological aging, as assessed by PhenoAge acceleration. Compared to participants with poor diet quality, those with high diet quality showed higher CVH (log) scores (β = 0.124 [0.026, 0.223], p = 0.013). Age and sex interactions were noted, with older adults (50 years and above) and males displaying stronger associations. No significant effects of sleep mediating the relationship between diet quality and CVH or biological aging were observed.

Conclusion: This dissertation suggests that emphasizing healthy dietary patterns (such as the plant-based diet) and sleep duration promotes cardiovascular health and delays biological aging. Findings indicate that the rPDQS can be a valuable screening tool to identify at-risk individuals with suboptimal dietary patterns, and along with sleep duration assessments, may optimize health screening and preventive health strategies.