Outcomes and Prognostic Factors in 267 Patients with Severe Acute Respiratory Syndrome in Hong Kong

Outcomes and Prognostic Factors in 267 Patients with Severe Acute Respiratory Syndrome in Hong Kong

Kin Wing Choi, MBChB, MRCP;
Tai Nin Chau, MBBS, MRCP;
Owen Tsang, MBChB, MRCP;
Eugene Tso, MBBS, MRCP;
Ming Chee Chiu, MBChB, MRCP;
Wing Lok Tong, MBBS, MRCP;
Po Oi Lee, MBBS, FRCR;
Tak Keung Ng, MBBS, FRCPath;
Wai Fu Ng, MBBS, FRCPath;
Kam Cheong Lee, MBBS, FRCPath;
William Lam, MBBS, FRCPA;
Wai Cho Yu, MBBS, FCCP;
Jak Yiu Lai, MBBS, FRCP;
Sik To Lai, MBBS; and
the Princess Margaret Hospital SARS Study Group*

From Princess Margaret Hospital, Hong Kong, China.

Abstract

Background: Severe acute respiratory syndrome (SARS) has become a global public health emergency.

Objective: To evaluate the characteristics and outcomes of patients with SARS in Hong Kong and to identify predictors of mortality.

Design: Retrospective cohort study.

Setting: Quarantine hospital for patients with SARS in Hong Kong.

Patients: 267 consecutive patients hospitalized from 26 February to 31 March 2003 for probable or confirmed SARS.

Measurements: Clinical, laboratory, and radiographic measures; 3-month mortality rate.

Results: According to our case definition, there were 227 cases of confirmed SARS and 40 cases of probable SARS. Common presenting symptoms were fever (99% of patients), chills (74%), malaise (63%), and myalgia (50%). Laboratory findings included lymphopenia (73%), thrombocytopenia (50%), hyponatremia (60%), and elevated levels of lactate dehydrogenase (47%) and C-reactive protein (75%). During hospitalization, incidence of diarrhea (53%), anemia (53%), and acute renal failure (6%) increased. Sixty-nine patients (26%) required intensive care because of respiratory failure. The 3-month mortality rate was 12% (95% CI, 8% to 16%). Factors contributing to mortality were respiratory failure, acute renal failure, and nosocomial sepsis. On multivariate Cox regression, age older than 60 years (relative risk, 5.10 [CI, 2.30 to 11.31]; P < 0.001) and lactate dehydrogenase level greater than 3.8 µkat/L at presentation (relative risk, 2.20 [CI, 1.03 to 4.71]; P = 0.04) were independent predictors of mortality.

Conclusion: Because of the longer follow-up period in our cohort, the mortality rate in these patients is higher than rates reported in previous studies. Advanced age and high lactate dehydrogenase level at presentation predict mortality.

*For members of the Princess Margaret Hospital SARS Study Group, see the Appendix.

Article and Author Information

Acknowledgments: The authors thank the staff of the Department of Medicine and Geriatrics, Princess Margaret Hospital, for their selfless devotion in the management of patients with SARS in Hong Kong. They also thank Ms. Esvin Chan and Ms. Linda Lu for secretarial assistance.
Grant Support: By the Hospital Authority of Hong Kong.
Potential Financial Conflicts of Interest: None disclosed.
Requests for Single Reprints: Sik To Lai, MBBS, Department of Medicine and Geriatrics, Princess Margaret Hospital, Lai King, Kowloon, Hong Kong, China; e-mail, lstpmh{at}netvigator.com.
Current Author Addresses: Drs. Choi, Chau, Tsang, Tso, Chiu, Tong, Yu, J.Y. Lai, and S.T. Lai: Department of Medicine and Geriatrics, Princess Margaret Hospital, Lai King, Kowloon, Hong Kong, China.
Drs. T.K. Ng, W.F. Ng, K.C. Lee, and Lam: Department of Pathology, Princess Margaret Hospital, Lai King, Kowloon, Hong Kong, China.
Dr. P.O. Lee: Department of Radiology, Princess Margaret Hospital, Lai King, Kowloon, Hong Kong, China.
Author Contributions: Conception and design: K.W. Choi, T.N. Chau, O. Tsang, E. Tso.
Analysis and interpretation of the data: K.W. Choi, T.N. Chau, O. Tsang.
Drafting of the article: K.W. Choi.
Critical revision of the article for important intellectual content: K.W. Choi, T.N. Chau, O. Tsang, E. Tso, W.C. Yu, J.Y. Lai, S.T. Lai.
Final approval of the article: K.W. Choi, T.N. Chau, O. Tsang, W.C. Yu, J.Y. Lai, S.T. Lai.
Provision of study materials or patients: P.O. Lee, T.K. Ng, W.F. Ng, K.C. Lee, W. Lam.
Statistical expertise: K.W. Choi, T.N. Chau, O. Tsang.
Obtaining of funding: S.T. Lai.
Administrative, technical, or logistic support: O. Tsang, S.T. Lai.
Collection and assembly of data: K.W. Choi, T.N. Chau, O. Tsang, E. Tso, M.C. Chee, W.L. Tong.