The data from the survey, which was conducted by the Dr. Ricardo Jorge National Institute of Health (INSA) and published on Monday, World Patient Day, point to 3.9 million people having at least one chronic disease from a list of 20.

The 20 diseases were arterial hypertension, acute myocardial infarction, stroke, cardiac dysrhythmia, diabetes, chronic renal failure, cirrhosis, chronic hepatitis, asthma, chronic obstructive pulmonary disease, chronic pain, osteoporosis, rheumatoid arthritis, arthrosis, cancer, depression, chronic anxiety, gastric or duodenal ulcer, high cholesterol and allergy.

Asked whether they have "some disease or health problem that has lasted for more than six months or if they expect it to last more than six months, more than half of respondents (57.8%) said they did.

Almost 20% of respondents (19.4%) said they had one chronic pathology, 17% cited two and 10.4% reported three. The data also indicate that 5.2% of the patients suffer from four chronic pathologies, 3% from five and 2.7% from six.

The occurrence was more frequent in women (62%) than in men (53.1%), in people with less schooling and in the age group of 65-74 years, the INSA data show.

In men, the most frequent chronic diseases were hypertension (25.1%), high cholesterol (23.7%), allergy (11.4%), diabetes (10.4%), chronic pain (7.4%) and arthrosis (7.3%). In women, the most indicated chronic diseases were hypertension (26.1%), high cholesterol (25.7%), arthrosis (20.6%), allergy (18.1%), depression (15.2%) and chronic pain (13.5%).

The survey was conducted with the participation of 4,911 people, mostly of working age (84.3% aged between 25 and 64 years), of whom about three fifths (63.4%) were "without schooling or with lower secondary education" and 11.2% were unemployed.

The purpose of the INSEF is to contribute to improving the health of the population, supporting national and regional activities of observation and monitoring of the state of health, assessment of health programmes and public health research.