The present study included data from 101.426 prescriptions for PE cases from Greece during 2013–2017. According to our results. PE prevalence is 23.79 cases per 100,000 population for 2017 that seems to be lower than previously published reports from other countries [3, 4]. Moreover, we revealed that there is an ascending tendency in PE prevalence from 2013 to 2017 that may reflect the progress in diagnostic tests in this field. Ageand gender distributionsis in agreement with other researches.
The PE annual prevalence for 2017 was estimated to 23.79 per 100,000 population in Greece. The reported trends in PE are lower than previously reported by others studies. To our knowledge this is the first study to describe the prevalence of PE in the general population of a country. Most studies report data on PE prevalence for in-hospital population. The prevalence of PE has been reported as high as 37% among selected hospitalized patients [12] while others reported a prevalence of 0.6% for subjects reporting syncope in the emergency department [13] and 16.1% in patients suffering from acute exacerbation of pulmonary embolism [14]. We have estimated PE prevalence by assessing the number of prescriptions by Social Security Number so that we would not have patient replicates counted more than one time so our study gives a rather fair estimate of the disease prevalence on the general population of Greece.
We observed annual increases in PE prevalence in the 4 years studied. PE prevalence raised from 5.43 cases per 100.000 population in 2013 to 23.79 in 2017. In addition, a slight increase was observed in the prevalence of PE with acute right heart dysfunction. Our data revealed a female predominance of PE prevalence throughout the study period consistent with the higher frequency of the disease in females [15]. Our results are in accordance with earlier published data [5, 8, 15–19], indicating a rising trend in PE case rates all over the years. We have previously reported an increase in PE incidence in Greece and a rather small mortality rate for the years preceding our study [15]. The increase in PE prevalence may be attributed to the wide availability and use of CT imaging among clinicians [5]. The correlation of the increase in PE prevalence may be additionally associated within creased prevalence of venous thromboembolism associated risk factors such as aging, heart failure and obesity [20, 21].
Our results provide further support to the age-dependent increase in VTE risk. We have observed increased PE prevalence in older subjects with a peak at the age groups 80–90 years for both genders. Our findings are consistent with previously published data. Other studies showed that incidence rates of PE in elderly patients are three times as high when compared to younger patients [22].
Additionally, in our research we found that the increase in PE prevalence was evident in both genders although females have a higher rate of prevalence increase throughout the study period The reasons underlying the gender differences cannot be addressed on the present study, however we hypothesize that discrepancies in life expectancy amongst sexes may at least in part provide an explanation. During the study period, the life expectancy of females ranged from 84.00 to 83.90 years (from 2013 to 2017, respectively) while life expectancy in males varied from 78.70 to 78.80 (from 2013 to 2017, respectively) and constantly remained lower than those for women [23].
In our study, we observed that patients with PE choose 51% of public health services versus 48% of the private sector. Also, we demonstrated that patients with PE are followed-up usually by a Pulmonologist than other specialties. This probably reflects the distribution of PE hospitalizations in Greece where there is anecdotal evidence that patients suffering from PE (occurring in the outpatient setting) are hospitalized mainly in Respiratory Medicine Departments. Venous thromboembolism is a multifactorial disease and may require multidisciplinary approach involving almost any medical specialty but more commonly Pulmonologists, Cardiologists and Hematologists. Our results reflect the national distribution of PE follow-up trends and highlight the need for national training programs for PE that aim in these specialties (both in the Public and Private sector).
Our study has several strengths and limitations. This is the first report of PE prevalence in Greece, with recent data from the entire Greek population. However, our study is of retrospective nature while we did not have available data on demographics of the cases (besides age, gender and health provider) or VTE related risk factors like cancer or hormone-replacement therapy. Additionally, data on PE with acute cor pulmonale were based on physician reporting and not on a standard definition of acute cor pulmonale. Therefore, we suppose that most of the cases reported as PE with acute cor Pulmonale may reflect patients with High risk PE (according to international guidelines [24]), however we cannot exclude that some patients would be classified as Intermediate-high risk PE.