Older patients tend to show fewer symptoms and abnormal lab results typically associated with ocular sarcoidosis than younger patients, making diagnosis more difficult, a study has found.
These findings highlight the need for more studies to explore and find other types of symptoms that could assist with disease diagnosis in older patients.
The study, “Age-related differences in the clinical features of ocular sarcoidosis,” was published in the journal PLOS ONE.
Ocular sarcoidosis is a type of sarcoidosis that causes inflammation, swelling, and destruction of eye tissues, a set of symptoms that fall under the general term uveitis.
Previous studies found that in developed countries, such as the U.S., Japan, and those in Europe, the incidence of ocular sarcoidosis has decreased among younger people, and the age of diagnosis has shifted toward older age groups.
Typically, sarcoidosis diagnosis involves a biopsy of the affected tissues. However, this procedure is not performed in patients with uveitis suspected of ocular sarcoidosis, because it is extremely invasive and can cause vision loss.
In 2009, the International Workshop on Ocular Sarcoidosis (IWOS) created a set of guidelines classifying uveitis patients into four categories — definite, presumed, probable, and possible ocular sarcoidosis — intended to assist with disease diagnosis.
Although a definite diagnosis of ocular sarcoidosis still requires a biopsy, considerable efforts have been made to define clinical signs and lab results crucial for an accurate diagnosis of sarcoidosis in uveitis patients.
In systemic sarcoidosis, previous studies reported that symptoms change as patients age. However, these age-related differences in ocular sarcoidosis-related symptoms had never been addressed.
In this study, researchers aimed to compare clinical symptoms and lab results between younger and older patients diagnosed with uveitis associated with ocular sarcoidosis, according to the IWOS criteria, to investigate the influence of age on clinical disease presentation.
The retrospective study analyzed 100 patients with ocular sarcoidosis from April 2010 to March 2016. Of these, 50 were considered older (with an age at diagnosis over 65), and the remaining 50 were considered younger (with an age at diagnosis of 65 or under).
All patients were examined to determine the presence of typical ocular symptoms of disease and specific parameters in lab tests.
Results showed that patients in the older group had significantly fewer ocular symptoms of disease, with the mean number of positive ocular signs being 2.8 versus 3.6 in the younger group. They also had fewer abnormal lab test results, with a mean number of positive lab tests of 1.5 versus 2 in younger patients.
More specifically, “the frequencies of keratic precipitates [inflammatory deposits in the cornea] (KP), vitreous opacities [small spots drifting in the field of vision] (VO) and bilateral inflammation were significantly higher in the younger group (64%, 78% and 80%, respectively) than in the elder group (40%, 60% and 64%, respectively),” the researchers wrote.
“For the laboratory examinations, BHL [enlargement of lung lymph nodes, bilateral hilar lymphadenopathy] was significantly more common in the younger group (78%) than in the elder group (52%),” they said.
In addition, researchers found a negative correlation between the patient’s age and the number of ocular symptoms and lab test results detected, suggesting that the older the patient is, the fewer the typical ocular symptoms experienced.
These findings indicate that older patients show fewer positive signs of disease and lab test results, making the diagnosis of ocular sarcoidosis more difficult in this age group. To circumvent this problem, the team recommends alterations in the IWOS criteria, and new studies that address symptom manifestations in older patients.
“Probable or possible ocular sarcoidosis by the international criteria should increase with increased life expectancy in developed countries. Further study to find novel symptom manifestations may be helpful in the diagnosis of ocular sarcoidosis in elderly patients,” they said.