Arthritis Diagnosis, Self-Rated Health, and the Period Pattern in Arthritis Prevalence

Arthritis is one of the most common chronic conditions with a prevalence that increases
with age, particularly among adults with comorbid conditions. Diagnosis as a medical process
connects patients with medical care, whereas health insurance status may influence how long a
person has illness symptoms before they receive a diagnosis. Progressing arthritis can change
one's health status significantly. The distribution of healthcare resources also varies by health
insurance status, which may impact individuals’ access arthritis care. Cohort and period effects
may affect the prevalence of arthritis over time due to changes in wealth, education attainment,
health insurance status and increasing BMI. This study investigates the relationship between
health insurance status and the time one reports arthritis diagnosis, the relationship between
arthritis diagnosis and self-rated health, and cohort and period effects in arthritis prevalence. I
address these research questions using data from Midlife in the United States (MIDUS) and
Health and Retirement Study (HRS) where I test hypotheses using a variety of statistical models.
In the first empirical chapter, I examine the relationship between health insurance status
(coverage and type) and the time at which a person self-reports an arthritis diagnosis using data
from three waves of MIDUS and panel-data survival analysis. Results indicate that respondents
who reported arthritis symptoms who were covered by public health insurance took longer to
report arthritis diagnosis than their privately insured counterparts.
In the second chapter, I investigate the relationship between arthritis diagnosis and selfrated health (physical and mental) using data from three waves of MIDUS and growth curve
models. Results demonstrate that having baseline private health insurance coverage moderates
the relationship between arthritis diagnosis and self-rated physical health. Symptomatic
individuals with arthritis diagnosis benefitted from baseline private health insurance coverage
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and reported better self-rated physical health than their counterparts who were not covered by
private health insurance.
In the final empirical chapter, I use fourteen waves of the Health and Retirement Study
(HRS, 1992-2018) along with hierarchical age-period-cohort (HAPC) models to study cohort and
period effects on the prevalence of self-reported doctor-diagnosed arthritis over time. Factors
that predicted significantly higher risk of arthritis, independent of period, include age and high
BMI. Wealth explained away cohort effects for pre-War Baby Cohorts and period effects from
survey year 2006 to 2018.
Overall, under the guidance of fundamental cause theory and sociology of diagnosis
theory, my dissertation provides empirical evidence on the role of health insurance status as a
form of flexible resource in predicting the timeliness of an arthritis diagnosis, and as a moderator
in the arthritis diagnosis—self-rated health relationship. Private health insurance also lowered
one’s likelihood of reporting arthritis over time. My findings contribute to systematic
examination of the role of health insurance status in the persistent of health inequality in the field
of medical sociology.