1 2 1
Joint Scientific Meeting of the International Epidemiological Association European Epidemiology Federation (IEA EEF)
& the Spanish Society of Epidemiology (SEE)
Gac Sanit 2003;17(Supl 2):51-198
DETERMINANTS OF B-TYPE NATRIURETIC PEPTIDE VARIABILITY
IN THE POPULATION
Ana Azevedo*, Paulo Bettencourt**, Rui A. Rodrigues***, Pedro B Al-
meida***, Margarida Alvelos**, Fernando Frioes**, Paula Dias***, Cas-
siano A. Lima***, Henrique Barros*
*Hygiene and Epidemiology, University of Porto Medical School, Porto, Portugal. **Ser-
viço de Medicina B, Hospital de S. João, Porto, Portugal. ***Serviço de Cardiologia,
Hospital de S. João, Porto, Portugal.
Introduction:
There is wide overlap of B-type natriuretic peptide (BNP) plas-
ma levels between people with and without heart failure (HF) and/or left ventri-
cular systolic dysfunction (LVSD). Thus performance of BNP for detection of LVSD
at the community level is suboptimal. The aim of this study was to identify de-
terminants of plasma BNP levels at the populational level.
Methods:
In a cross-sectional study, we evaluated 559 participants selected from
the community-dwellers of Porto aged 45 years or older by random digit dialing.
Participants answered a questionnaire and were submitted to a clinical exami-
nation, ECG, echocardiogram and venous blood sample collection. BNP was
measured by the BIOSITE® Triage meter. The association between BNP and
independent variables was assessed by linear regression using the natural lo-
grithm of BNP plasma concentration as the dependent variable.
Results:
BNP levels were significantly higher in women than in men and this
association was not changed when taking into account other determinants of
BNP. Further analysis was stratified on gender. BNP increases with age, more
steeply in men than women (p<0.05 for the interaction). In univariate analysis,
BNP was associated in both men and women with LVSD, moderate-severe val-
vular abnormalities, left atrial diameter/body surface area, left ventricular mass
index, systolic blood pressure, lower creatinine clearance and jugular venous
distention on physical examination. In women it was also related with end-dias-
tolic left ventricular diameter/body surface area and in men with changes in the
segmental wall motion index. The final multivariable model includes as signifi-
cant independent determinants of BNP levels: age, LVSF and left atrial dimen-
sion among women, and age, LVSF and systolic blood pressure among men.
These models explain 17.2% and 32.3% of the variability of BNP, respectively
in women and men.
Conclusion:
The main determinants of BNP plasma levels in the population were
female gender; age and left ventricular systolic dysfunction in both genders; left
atrial size in women and systolic blood pressure in men. The association bet-
ween age and BNP was significantly stronger among men than women.
240
FAMILY HISTORY OF VENOUS DISEASES IN PATIENTS WITH VA-
RICOSIS - RESULTS OF A POPULATION-BASED CROSS-SEC-
TIONAL STUDY.
Katja Bromen
1
, Andreas Stang
1
, Eberhard Rabe
2
, Katrin Schuldt
1
, Su-
sanne Weber
1
, Eva Bock
1
, Felizitas Pannier-Fischer
2
, Karl-Heinz Jöckel
1
1
Institute for Medical Informatics, Biometry and Epidemiology, Medical Faculty, Uni-
versity of Essen, Essen, Germany.
2
Department of Dermatology, University of Bonn,
Bonn, Germany.
Introduction:
Diseases of the venous system belong to the most frequent diseases
in the German population. However, the last comprehensive population-based Ger-
man data stem from a study conducted in Tübingen in 1979. Since then, diagnostic
methods have improved substantially. Also, the risk factor exposure has changed, e.g.
lack of exercise, sedentary occupations. Practical experience and scientific studies in-
dicate a familial predisposition to this disease. We examined this issue using actual
epidemiologic data.
Methods:
We conducted a population-based cross-sectional study in Bonn and its su-
rrounding rural area (Recruitment period: 11/2000-12/2001; response: 59%) funded by
the Federal Ministry of Health and the German Society of Phlebology. The study po-
pulation comprised 3072 participants, 18 to 79 years of age. The investigation consis-
ted of ascertaining a standardized medical history, physical examination, and duplex
sonography of veins of the legs. The definition of varicosis of the leg is based upon the
CEAP-Classification. 2 outcome definitions were used: 1) Participants were defined as
having varicose veins if the clinical classification was at least C2, 2) Symptomatic va-
ricose veins, i.e. clinical classification of at least C3. In both groups, those showing iso-
lated spider-bursts / telangiectasia exclusively and those with exclusive postthrombo-
tic etiology were excluded. Risk factors examined were family history of varicose veins
(VV), thrombophlebitis of the legs (TL), deep venous thrombosis of the leg (VT), and
crural ulcer (CU). Logistic regression, adjusted for age, sex and family size was used
for calculation of odds ratios (OR) and 95% confidence intervals (95%-CI).
Results:
713 study participants (23%) had varicose veins with clinical classification
of at least C2 (20% of all men, 26% of all women). 295 study participants (10%) sho-
wed symptomatic varicose veins as defined above (8% of all men, 11% of all women).
Prevalences of family history (parents and siblings) were as follows: VV: 52%, TL: 14%,
VT: 13%, CU: 8%. Results of the logistic regression were as follows: 1) Varicose veins:
VV: OR=2.2 (95%-CI:1.8-2.6), TL: OR=1.9 (95%-CI:1.5-2.4), VT: OR=1.6 (95%-CI:1.2-
2.0), CU: OR=2.0 (95%-CI:1.5-2.7). 2) Symptomatic varicose veins: VV: OR=1.7 (95%-
CI:1.3-2.2), TL: OR=1.5 (95%-CI:1.1-2.1), VT: OR=1.4 (95%-CI:1.0-2.0), CU: OR=1.8
(95%-CI:1.2-2.5). Including the information on grandparents did not lead to relevant
changes in results.
Conclusions:
The association between family history of various forms of venous di-
seases and varicosis was confirmed by the results of this study.
241
DISEASE-RELATED COSTS IN PATIENTS WITH HYPERCHOLES-
TEROLEMIA
Jacqueline Müller-Nordhorn
1
, Heike Englert
1
, Frank Sonntag
2
, Heinz
Völler
3
, Eberhard Windler
4
, Wolfgang Meyer-Sabellek
5
, Hugo Katus
6
,
Karl Wegscheider
4
, Stefan N Willich
1
1
Institute of Social Medicine, Epidemiology, Health Economics, Charité Hospital, Ber-
lin, Germany.
2
Cardiologist, Henstedt-Ulzburg, Germany.
3
Rehabilitation Centre for Car-
diovascular Diseases, Rüdersdorf, Germany.
4
University of Hamburg, Germany.
5
As-
traZenaca GmbH, Wedel, Germany.
6
University of Heidelberg, Germany.
Introduction:
Hypercholesterolemia (HC) is a major risk factor for cardiovascu-
lar diseases. In a cost-of-illness analysis we aimed to assess direct and indirect
costs of patients withHC.
Methods:
The present analysis is part of the ongoing ORBITAL study, a rando-
mised controlled trial evaluating the long-term cost-effectiveness of a complian-
ce enhancing programme in 8000 patients with HC requiring statin therapy ac-
cording to Joint European Guidelines. At baseline patients were asked
retrospectively about their medical resource use and employment status in the
six months preceding enrolment. Direct cost data (including for the present analy-
sis costs for ambulatory, hospital, rehabilitative and nursing care, physiotherapy
and transportation) were calculated by multiplying medical resource units used
with cost factors per unit. Indirect cost data (productivity loss) were calculated
by multiplying days off work due to illness or disease-related early retirement with
the average cost factor per day (societal perspective).
Results:
Among a total of 2500 patients (mean age 61 ± 11 years, 44% fema-
le) included in the present analysis, 32% were employed at the time of inclusion,
19% had a history of myocardial infarction, 8% a history of stroke, 61% had hy-
pertension and 28% diabetes. Disease-related direct costs amounted to a mean
of 655 Euros ± 2293 per patient in the six months period, indirect costs to a mean
of 1495 Euros ± 4124 per patient. Direct costs included mainly costs for hospi-
tal stays (433 Euros ± 2098), primary care consultations (111 Euros ± 118), out-
patient therapeutic measures (54 Euros ± 200), and rehabilitation (43 Euros ±
367). Indirect costs due to days off work amounted to 303 Euros ± 1485, due to
early retirement to 1191 Euros ± 3940. Of all patients, 11% (n=287) reported days
off work (median 14 days) and 9% (n=214) reported disease-related early reti-
rement.
Conclusions:
Indirect costs due to a loss of productivity contributed markedly
to the disease-related costs in patients with HC. The considerable economic bur-
den of HC indicates the need to assess long-term effectiveness of health care
programmes in patients with the disorder.
238
HIGH SENSITIVITY C-REACTIVE PROTEIN AND THE FEATURES
OF THE METABOLIC SYNDROME
Ana C Santos*, João T Guimarãaes**, Mario Cerqueira-Gomes***, Hen-
rique Barros*
*Department of Hygiene and Epidemiology, University of Porto Medical School, Porto,
Portugal. **Department of Immunology, University of Porto Medical School, Porto, Por-
tugal. ***Unit of Cardiovascular Research and Development, University of Porto Me-
dical School, Porto, Portugal.
Introduction:
The metabolic syndrome components, including central obesity, high
blood pressure and glucose resistance, are major cardiovascular risk factors and
have recently been associated with elevated levels of the acute phase reactant,
C-reactive protein (CRP). We aimed to evaluate the association between the le-
vels of CRP and the features of the metabolic syndrome in an urban sample of
community dwellers.
Methods:
We evaluated 498 adult subjects (306 women and 192 men), 18-92 years,
recruited after random sampling of Porto in-habitants. All participants completed
a structured questionnaire comprising information on social, demographic, beha-
vioural and clinical aspects. Anthropometrics and blood pressure were recorded
and a fasting blood sample collected. Metabolic syndrome was defined according
to the Third Report of the Expert Panel on Detection, Evaluation, and Treatment
of High Blood Cholesterol in Adults, as the presence of 3 or more of the following
characteristics: waist circumference greater than 102 cm in men and 88 cm in women,
triglycerides levels
≥
150mg/dL, high density lipoprotein cholesterol (HDL)
≤
40 mg/dL
in men and
≤
50mg/dL in women, blood pressure
≥
130/85 mm Hg and serum glu-
cose
≥
110mg/dL. High-sensitivity CRP was assessed by nephelometry. Means were
compared after log transformation using ANOVA.
Results:
Median CRP levels were significantly higher (p<0.05) in the presence of
central obesity (2.8mg/L vs. 1.2mg/L), high blood pressure (1.9mg/L vs. 1.0mg/L)
and hypertriglyceridemia (2.0mg/L vs. 1.4mg/L). In the presence of metabolic syn-
drome higher median levels of CRP (2.7 mg/L vs. 1.4 mg/L, p<0.001) were also
observed. We also found a significant increasing trend (p<0.001) in median levels
of CRP with increasing number of components of the metabolic syndrome.
Conclusions:
The present data supports the hypothesized role of inflammation
in the development of several features of the metabolic syndrome, namely obe-
sity and hypertension. Moreover it also seems that increasing severity of meta-
bolic syndrome is associated with increasing inflammation. The metabolic syndrome
seems to be associated with a systemic inflammatory response, which may re-
present an additional pathway for coronary heart disease in these subjects.
239