Abstract
Purpose::
Recent molecular and serological data have suggested a link between rubella infection and Fuchs' heterochromic iridocyclitis (FHI). This study was designed to investigate the epidemiological relationship between FHI and the institution of the rubella vaccination program (RVP) in the US in 1969.
Methods::
A retrospective chart review of patients seen at the uveitis service of the University of Illinois Eye and Ear Infirmary between 1985-2005 with FHI was performed. Patients with idiopathic chronic iridocyclitis (iCIC) and idiopathic chronic granulomatous iridocyclitis (iCGIC) seen during the same time interval served as controls. All subjects were separated by decade of birth, and the percentage of each condition per decade was calculated. Trend analysis allowed measurement of statistical significance across time. A second analysis measured the percentage of patients with FHI, iCIC, and iCGIC, who were born outside the US per decade.
Results::
A total of 3856 patients were seen between 1985-2005. The overall breakdown in this study was: 3.40% FHI (n=131), 7.47% iCIC (n=288) and 4.36% iCGIC (n=168). The percentage of FHI per decade in this series has decreased in subjects targeted by the RVP. Prior to 1959, FHI comprised 3.51-5.19% of total uveitis cases. After the introduction of the RVP in 1969, the percentages have been 0.62-1.18% of total uveitis cases. A decrease was noted in patients born between 1959-1969 (2.97%), as they were also targeted by the RVP. The change across time observed in FHI patients was significantly different than the trend seen for iCIC (p=0.0007) and iCGIC (p=0.0002), while the two control groups were not significantly different from one another (p=0.5437). An increase in the percentage of foreign-born patients with FHI was seen after the institution of the RVP (42-55%) compared to FHI patients born in previous decades (24-25%). The percentage of foreign-born patients with iCIC has actually decreased in recent years, while the number with iCGIC has remained relatively low.
Conclusions::
The relative percentage of FHI in this series has decreased in patients born after the introduction of the RVP in the US and in those patients born in the previous decade who were eligible to receive the vaccination. The percentage of patients with FHI born outside the US has also increased in recent decades. This epidemiological study supports a relationship between the rubella virus and FHI, as suggested by previous studies.
Keywords: uveitis-clinical/animal model • clinical (human) or epidemiologic studies: prevalence/incidence • clinical (human) or epidemiologic studies: biostatistics/epidemiology methodology