Table 22.

—[Section 3.3] Summary of Findings: Rivaroxaban vs Placebo for Extended Anticoagulation of VTE^a,b,88

Outcomes	No. of Participants (Studies), Follow-up	Quality of the Evidence (GRADE)	Relative Effect (95% CI)	Anticipated Absolute Effects
				Risk With Placebo	Risk Difference With Rivaroxaban (95% CI)
Mortality	1,196 (1 study), 6 or 12 moc	Moderated,e due to imprecision	RR 0.49 (0.04-5.4)f	3 per 1,000	2 fewer per 1,000 (from 3 fewer to 15 more)
Recurrent VTE	1,196 (1 study), 6 or 12 moc	Highd	HR 0.18 (0.09-0.39)	71 per 1,000g	58 fewer per 1,000 (from 43 fewer to 64 fewer)
Major bleeding	1,188 (1 study), 6 or 12 mo	Moderated,h due to imprecision	RR 4.9 (0.58-42)f	i	7 more per 1,000 (from 3 more to 16 more)
Burden of anticoagulation not reported	…				Rivaroxaban: daily medication
PTS not reported	…	…	…	…	j

The basis for the assumed risk (eg, the median control group risk across studies) is provided in footnotes. The corresponding risk (and its 95% CI) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI). Working group grades of evidence are as follow: High quality, further research is very unlikely to change our confidence in the estimate of effect; moderate quality, further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate; low quality, further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate; very-low quality, we are very uncertain about the estimate. See Table 1, 3, and 21 legends for expansion of abbreviations.

^aIncluded patients had acute, symptomatic, and objectively verified proximal DVT of the legs or PE (unprovoked, 73%; cancer, 5%; previous VTE, 19%).

^bRivaroxaban 20 mg/d for 6 or 12 mo after initial long-term therapy.

^cFollow-up was prespecified to be 6 (60%) or 12 (40%) mo.

^dAllocation was concealed. Patients, providers, data collectors, and outcome adjudicators were blinded. Intention-to-treat analysis; 0.2% were loss to follow-up. Not stopped early for benefit.

^eCI includes values suggesting benefit or no effect; relatively low number of events.

^fCalculated from reported data with addition of one event to each event rate because event rate was 0 in the control group.

^gOne definite or possible fatal VTE in the rivaroxaban group and one in the LMWH/VKA group.

^hCI includes values suggesting benefit and harm.

ⁱBleeds contributing to death: none in the rivaroxaban group and none in the warfarin group.

^jPTS: baseline risk over 2 y of 58.8% for PTS and 13.8% for severe PTS (Kahn et al¹⁰²). There is threefold (Prandoni et al²⁰²) to 10-fold (van Dongen et al²⁰⁹) increase in PTS with recurrent VTE in the ipsilateral leg.