We will conduct a four-year, observational study of 850 participants to measure physical activity and diet, once a year for three years. All participants will also complete the standard Centers for AIDS Research (CFAR) Network of Integrated Clinical Systems (CNICS) patient-reported outcomes (PRO) and clinical assessment procedures. An enhanced PRO assessment (consisting measures of physical activity, diet intake and anthropomorphic factors) will be included after the routine patient clinic visit at four CNICS sites: Case Western Reserve University, University of Alabama at Birmingham, University of Washington, and Fenway Health.

PROSPER-HIV is a four-year, prospective, observational study of 850 CNICS participants who will complete an enhanced patient-reported outcome (PRO) assessment to measure physical activity and diet intake, once a year for three years. All participants will also complete the standard CNICS PRO and clinical assessment procedures. We propose to integrate the following measures, physical activity (triaxial accelerometery), dietary intake (24-hour diet recalls), and anthropomorphic factors (waist-hip-ratio), into an enhanced annual assessment of patient reported outcomes at four CNICS sites: Case Western Reserve University, University of Alabama at Birmingham, University of Washington, and Fenway Health. Our four primary objectives are to:

1. Identify and characterize longitudinal, objectively measured, physical activity and dietary patterns among PLHIV
2. Examine the relationship between objectively-measured physical activity and self-reported physical activity on the Lipid Research Clinics Physical Activity Questionnaire.
3. Determine which aspects of physical activity patterns and diet quality are associated with decreased symptom burden and intensity in PLHIV, and if this relationship is moderated by age and sex.
4. Explore the potential mediating effect of anthropomorphic and physical fitness variables on the relationships between physical activity, dietary patterns, and symptom burden and intensity in PLHIV.

We hypothesize that people living with HIV who 1) have more intense, frequent and longer physical activity bouts will have age- and sex-dependent reduced symptom burden; 2) eat better quality diets (e.g., more fiber and protein, fewer carbohydrates) will have reduced symptom burden and intensity and that this relationship will also vary by age and sex.

Inclusion Criteria:

1. Be an active CNICS participant
2. aged ≥18 years
3. prescribed HIV antiretroviral therapy, and
4. have an undetectable HIV viral load: defined as the most recent HIV viral load <200 copies/mL, checked within the past year.

Exclusion Criteria:

1) Did not complete the HIV Symptom Index in the PRO assessment (2) No reliable access to a telephone or internet-enable telephone services needed to complete the 24-diet recalls (3) Was pregnant, breast-feeding, or planning a pregnancy at the time of PRO assessment (4) Planning to move out of the area in the next 36 months, or (5) Non-English speaking.

We will recruit and enroll 850 people living with HIV (PLHIV) who participate in the Centers for AIDS Research Network of Integrated Clinical Systems cohort to participate in this longitudinal observational study.

Data will be shared consistent with the CNICS Data Sharing Policy found here: https://www.uab.edu/cnics/images/CNICSdatasharing\_policy\_v081515.pdf