The use of cemented fixation is widely recommended when hip arthroplasty is used to treat hip fractures. Some argue that the risk of bone cement implantation syndrome (BCIS), characterized by cardiovascular collapse at the time of cementing and pressurization, is so high it does not warrant the use of bone cement to reduce revision risk. We aimed to assess the association between cemented fixation and mortality and cardiopulmonary morbidity to assess this risk in a secondary analysis of data collected during the HIP ATTACK randomized clinical trial. The HIP ATTACK trial, was a 2,970-patient trial in which patients with a hip fracture that required surgery were randomized to accelerated surgery or standard care. We included all patients enrolled in the HIP ATTACK trial who had hemiarthroplasty or total hip arthroplasty for femoral neck fractures and who had their fixation status recorded. Due to the retrospective nature of this secondary analysis, we did not collect any additional data. Fixation was recorded in the trial data, as were mortality and morbidity after 90 postoperative days. We created a composite outcome, reflective of the cardiopulmonary risk factors associated with BCIS: all-cause mortality, myocardial infarction, stroke, congestive heart failure, new atrial fibrillation, coronary revascularization, venous thromboembolism, and pneumonia. We used logistic regression to measure the odds ratio (OR) of the association between cemented fixation and this composite outcome, while adjusting for several covariates: age (≤80 vs >80 years-old), sex, ethnicity (white vs non-white), revised cardiac risk index, chronic obstructive pulmonary disease (a risk factor for BCIS), dementia, and type of arthroplasty (hemi vs total hip). We identified 966 patients, 61% of which had cemented fixation. Although patients were randomized for time-to-surgery, the cemented and uncemented groups were also mostly balanced, with a similar median age (82 vs 79), proportion female (67% vs 70%), ethnicity (65% vs 59% white), and comorbidities. The type of arthroplasty differed, however, 89% of cemented and 76% of uncemented procedures were hemiarthroplasties. At 90 days, 19% of cemented fixation and 17% of uncemented fixation patients were affected by one of the events in the composite outcome, mostly death, myocardial infarction, and/or pneumonia. After adjustment for the factors mentioned above, we did not measure an increased risk of the composite outcome, the adjusted OR was 1.0 (95% confidence interval 0.7-1.4). We lacked the statistical power to investigate possible interaction by age, sex, or the type of procedure and could not assess whether differential effects in these strata were due to chance alone or might point to clinically-relevant effect modification. We found no association between cement use and a BCIS-related adverse composite outcome and found no evidence against established guidelines on the use of cement in arthroplasty for hip fractures.