The increased risk of venous thromboembolism by advancing age cannot be attributed to the higher incidence of cancer in the elderly: the Tromsø study

Abstract

Whether the high incidence of venous thromboembolism (VTE) in the elderly can be attributed to cancer is not wellstudied. We assessed the impact of cancer on risk of VTE in young, middle-aged and elderly. 26,094 subjects without a history of cancer or VTE were recruited from the Tromsø study. Incident cancer (n=2,290) and VTE (n=531) were recorded from baseline (1994-95) through December 31st, 2009. Cox regression with cancer as time-varying exposure was used to calculate hazard ratios with 95% confidence intervals (CI). Overt cancer was associated with a 5-fold (95%CI: 4.3, 6.7) increased risk of VTE, with an age-dependent gradient from 26-fold (95 %CI: 12.1, 56.5) increased in the young, 9-fold (95% CI: 6.6, 12.7) increased in the middleaged, and 3-fold (95 % CI: 2.5, 4.5) increased risk in the elderly. The population attributable risks were 14%, 27% and 18%, respectively. Conclusion: The relative risk of VTE by cancer were higher in young compared to elderly subjects, but the proportion of VTEs in the population due to cancer did not differ much across age groups. Our findings indicate that the increased risk of VTE by advancing age cannot be attributed to higher incidence of cancer in the elderly.

The European Hematology Association Roadmap for European Hematology Research: a consensus document

“…Recently, Blix et al calculated age-specific population attributable risks of VT due to cancer based on incidences of cancer and VT in the Tromsø Study and found a smaller actual difference than postulated between the young (<50 years, population attributable risk 14%) and the elderly (>70 years, population attributable risk 18%). 262 These findings show that malignancy does not explain a substantial proportion of the VT events in the elderly, and, most importantly, that studies focusing on risk factors in the elderly are urgently needed, because extrapolations do not suffice. A limited number of studies have investigated the impact of age-specific risk factor on VT risk, and prelimi- nary data have shown that thickening of the venous valves occurs with age, which may contribute to the high incidence of thrombosis in the elderly.…”

Venous thromboembolism in chronic lymphocytic leukemia: a Danish nationwide cohort study

“…[31][32][33][34] In the present study, the effect of age on the risk of VTE was surpassed by both second primary cancers following CLL diagnosis and previous VTE, which is in line with several studies in cancer populations where increasing age was not associated with increased risk of VTE. 11,[35][36][37] A higher risk of VTE was observed in periods when patients were exposed to CLL treatment than in periods of watch and wait, which has been shown in large studies and common cancers and indicated by the study on VTE in CLL byŠimkovič et al 7,9,[38][39][40][41] Interestingly, Simkovič et al 7 also mentioned a second cancer as a risk factor for VTE in CLL patients, but it was not further investigated, perhaps due to the study design and its aim.…”

Associations between serum levels of calcium, parathyroid hormone and future risk of venous thromboembolism: the Tromsø study

“…We also examined the apparent effects of discordant levels of PTH and calcium on VTE risk in a cause-specific analysis where subjects who developed MI, stroke or cancer were censored at the date of event. Events of MI, stroke and cancer were validated by an independently endpoint-committee as previously described (22,23,24).…”