Background: Long-term assessment of global function in post-critical illness patients allows referral to rehabilitation services and evaluation of acute care practices. Many patients resuscitated from cardiac arrest (CA) are lost to follow-up (LTFU), and it is unknown if these LTFU patients are similar or systematically different from other CA patients. We hypothesized patients LTFU would differ in resuscitation and outcome characteristics from those who are not LTFU.
Methods: Prospective cohort study of 252 English-speaking CA survivors between 2/1/16 and 11/31/18. We measured baseline demographic data and global functional outcome using Modified Rankin Scale (mRS), Cerebral Performance Category (CPC), and CPC-Extended (CPC-E) at hospital discharge, 3 and 6-months, and 1-year. We obtained contact information during the index hospitalization and attempted telephone assessments during one week blocks at the time after hospital discharge. We defined LTFU as failure to contact the patient or surrogate. We compared characteristics of those LTFU with those contacted using t-test and chi-square.
Results: Of 252 patients, 98 (38.8%) completed 3-month assessments and 83 (32.9%) were LTFU. At 6-months, 97 / 217 (44.7%) were LTFU, and at 1-year 41 / 117 (35.7%) were LTFU. The remainder were in hospital, in-patient rehab, missed by the research team, or dead. At 3-months, LTFU patients were younger (54 (SD 14) years vs. 59 (SD 16) years; p = 0.02), unmarried (53% vs 44%; p=0.01), and had longer ICU length of stay (8.4 (SD 10) days vs 5 (SD 5) days; p=0.008). At 6-month LTFU patients were more often female (p=0.02), and non-shockable rhythm (65% vs 47%; p=0.03). At 1-year, LTFU were more often non-shockable rhythm (61% vs 49%; p=0.01), younger (53 (SD 15) vs. 62 (SD 15) years; p=0.007) and with better functional score at 6-months (MRS 0-2 56% vs. 88%; p=0.04).
Conclusion: Over one-third of patients are LTFU during the year after CA. At 3 months no completion of assessment is associated with ongoing hospitalization, acute-care rehab, and death. LTFU is more common in patients who are younger, female, unmarried, have longer ICU length of stays, non-shockable rhythms, and better functional status at 6 months. Future research should account for the non-random distribution of patients LTFU.