Long COVID and Its Associations With Health Outcomes in Older Adults

Study Overview
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Brief Summary
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The Peking University Health Cohort in Anning, Yunnan (PKUHC-AN) is a prospective cohort study carried out in Anning, Yunnan. The primary aim of this study is to investigate the impact of COVID-19 on older adults' health, and to provide high-quality evidence of real world research for the optimization of prevention and control strategies of COVID-19 and other emerging infectious diseases. Data will be collected regarding health status, history of COVID-19 infections and vaccines, lifestyle and socioeconomic characteristics, as well as the short- and long-term health outcomes.

Detailed Description
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COVID-19 pandemic attributed to a great number of mortalities around the world in the last 3 years. About 46% of the global population are estimated to have been infected by the omicron variant and its sublineages. Health outcomes post COVID-19 has been of great concern globally since more and more people infected by SARS-CoV-2. Integrated efforts should be made to estimate the incidence of reinfections and long COVID in China, especially among older adults who are vunlerable and susceptible to COVID-19. In view of this, the Peking University Health Cohort Study in Anning, Yunnan aims to investigate the impact of COVID-19 on older adults' health, and to provide high-quality evidence of real world research for the optimization of prevention and control strategies of COVID-19 and other emerging infectious diseases. Data will be collected regarding health status, history of COVID-19 infections and vaccines, lifestyle and socioeconomic characteristics, as well as the short- and long-term health outcomes.

Official Title
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A Prospective Cohort Study for Long COVID and Health Outcomes in Older Adults in Yunnan, China

Conditions
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Long COVID, COVID-19 Pandemic, Elderly Infection, Vaccine Reaction, Lifestyle Factors, Reinfection

Intervention / Treatment
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* Other: no interventions


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 1. ≥60 years 2. Resided in Anning in the past half year and have no plan to move out in next 1 year 3. Older adults who are willing to participate in this study with informed consent Exclusion Criteria: 1. Unable to answer questions or communicate 2. Older adults who are not willing to participate in this study or without informed consent

Ages Eligible for Study
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Minimum Age: 60 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Exposure group<br>Group with history of COVID-19 infections and vaccines, as well as health-related, behavioral, socioeconomic exposures. | Other: no interventions<br>* This is an observational study without any intervention.<br>|
| Non-exposure group<br>Group without history of COVID-19 infections and vaccines, as well as health-related, behavioral, socioeconomic exposures. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of long COVID | The proportion of participants incurred any symptoms or diagnosed diseases of post-COVID in all infected participants. | From baseline until the date of long COVID symptoms or date of death from any cause, whichever came first, assessed up to 12 months. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Reinfection incidence of COVID-19 | The proportion of participants infected by COVID-19 at least 2 times. Measured by trained health professionals. | At 3 months, 6 months, 9 months, 1 year after baseline investigation. | 
| Cognitive impairment | Measured by health professionals using MMSE (Mini-Mental State Exam). The MMSE cognitive screening test is a 30-point questionnaire for analyzing several cognitive functions including memory, orientation, attention, calculation, and language. MMSE is measured on a scale between 0 and 30, where scores of 0-9, 10-20, 21-26, and 27-30 indicate severe, moderate, mild, and normal cognitive function, respectively. | At 3 months, 6 months, 9 months, 1 year after baseline investigation. | 
| Depression | Measured by health professionals using PHQ-9 (Patient Health Questionnaire-9). PHQ-9 provides a score ranging from 0 to 27, where scores of <4, 5-9, 10-14, 15-19, and 20-27 represented no, mild, moderate, moderately severe, and severe depression, respectively. | At 3 months, 6 months, 9 months, 1 year after baseline investigation. | 
| Medical expenditure | Measured by health professionals using self-designed questionnaire about their past month outpatient expenditure and past year inpatient expenditure. | At 3 months, 6 months, 9 months, 1 year after baseline investigation. | 
| Incidence of catastrophic health expenditure | Measured by health professionals using self-designed questionnaire about their households' past year consumption expenditure (including food expenditure, cloths expenditure, transportation expenditure and so on), and calculated as the proportion of households whose out-of-pocket medical expenditure exceed 40% of household non-food expenditure. | At 3 months, 6 months, 9 months, 1 year after baseline investigation. | 
| Sleep quality | Measured by health professionals using PSQI (Pittsburgh Sleep Quality Index). PSQI reflects sleep for a month, includes 18 items (7 subscales): subjective sleep quality, sleep latency, sleep duration, habitual sleep efficiency, sleep disturbance, use of sleeping medications, and daytime dysfunction. The range of PSQI global score is 0-21, and a score of >5 or 7 is indicative of poor sleep quality. | At 3 months, 6 months, 9 months, 1 year after baseline investigation. |