On average, people with Cushing’s syndrome wait 34 months before receiving a definite diagnosis, but waiting time largely depends on their specific disease subtype, a review study from Germany reports.
Cushing’s disease patients — those with a tumor in the pituitary gland — wait the longest for a confirmed diagnosis (38 months), while people with hormone producing tumors outside the pituitary or adrenal glands — ectopic Cushing’s syndrome — have the shortest waiting times (14 months), an analysis of published studies found.
Symptoms of Cushing’s syndrome often overlap with that of other diseases — like obesity, osteoporosis, and depression — meaning that patients can wait several years before a diagnosis is made. Meanwhile, an early diagnosis is important to preventing complications.
Researchers at the Ludwig-Maximilian University Clinic in Munich and colleagues conducted a literature review to determine the time that passes between a person’s first Cushing’s symptoms and diagnosis.
Their analysis included 44 studies published between 1969 and 2018, and an additional 172 patients followed at their tertiary care center, called the Munich cohort. In total, researchers reviewed time to diagnosis for 5,367 people.
In the Munich cohort, average time from first symptoms to diagnosis was four years (48 months), but some significant differences were observed when looking among disease subtypes.
Patients with adrenal Cushing’s syndrome in this group waited the longest for their diagnosis — 50 months — closely followed by those with Cushing’s disease (49 months). For those with ectopic Cushing’s syndrome, average waiting time was 34 months.
Average time to a diagnosis was also 34 months over the entire patient population. Again, differences were seen across subtypes, with pituitary and adrenal Cushing’s syndrome taking significantly longer to be correctly identified (38 and 30 months, respectively) compared to ectopic disease (14 months).
Researchers believe that the aggressive nature of ectopic tumors lead to more severe symptoms, including low blood potassium levels and high blood sugar, explaining why these tumors are found earlier.
Gender and year of diagnosis showed no impact on the time to diagnosis. No significant differences in diagnostic times were also seen between pediatric and adult cases.
The studies included in the meta-analysis were conducted in Germany, Italy, the United Kingdom, and the United States. When looking the largest subgroup of patients — those with Cushing’s disease, or pituitary Cushing’s — researchers found that longest time to diagnosis was in Germany (56 months), followed by the U.K. (39 months), Italy (35 months), and the U.S. (34 months).
These findings show “a clear difference in the time to diagnosis depending on the subtype of CS [Cushing’s syndrome], being shortest in ectopic CS,” the researchers wrote.
“Despite a multitude of improvements in the care of patients, we did not detect secular trends towards earlier diagnosis in pediatric patients or patients with more recent diagnosis,” they added. The team suggested this might be a result of the current higher prevalence of obesity, a condition whose symptoms largely resemble those of Cushing’s.
Researchers suggested that teaching general practitioners to recognize patterns of Cushing’s syndrome, along with “simple and effective biochemical screening approaches,” may significantly reduce the time these patients wait for a definitive diagnosis.