Objectives:
To identify the set of symptoms most frequently co-occurring with hypochondriacal complaints in patients with neurotic or personality disorders.

Methods:
Nonparametric Spearman rank correlations between the variables of symptom checklist “O” describing hypochondriacal symptoms and other symptoms were analyzed. To increase the reliability of the results, the analyses were performed independently in two groups: 3,929 patients before admission to a day hospital in the years 1980–2002 (group A) and 3,190 patients before admission in the years 2004–2015 (group B).

Results:
For selected groups of patients, lists of correlation coefficients were obtained showing the most important (strongest) and statistically significant associations between five hypochondriacal symptoms and somatization symptoms coming from the muscular system, breathlessness, symptoms coming from the cardiovascular system, anxiety symptoms, and compulsive thoughts without specific content.

Conclusions:
The multidimensional nature of hypochondriacal complaints and their association with somatization symptoms similar to infection or inflammation were confirmed. Apart from the fears about patient’s own health, fears about close relatives are also an important symptom, to which clinical attention should be paid.