Table 1.
Association between investigated factors and opioid non-response reported in 39 studies included in the systematic review
| Factors | Association [reference] | ||
|---|---|---|---|
| None | Direct | Inverse | |
| Sociodemographic | |||
| Age (advanced) | [22, 24, 25, 30, 36, 50, 51, 61, 77] | [53, 63, 83] | [38, 40, 57, 58, 65, 66, 78, 80, 81] |
| Gender (male) | [24, 25, 36, 38, 40, 47, 51, 57, 58, 61, 65, 66, 77, 78, 86] | [53, 83] | [22] |
| Weight/body mass index | Body mass index [51, 58] | Weight gain (higher or equal to 1 kg) [25] | |
| Alcohol | Alcoholism [28, 72] | Abuse [56] | |
| Clinical | |||
| Cancer diagnosis | [23, 24, 36, 38, 51, 58, 62, 77, 83] | Gastrointestinal, lung and ovarian [78]; mesothelioma [41]; lower gastrointestinal tract [25]; breast [53]; head and neck and lung [50]; tongue [46] | Non sex-related cancers [57] |
| Biochemical parameters | [35]; Serum creatinine and total bilirubin [53]; sodium, calcium, albumin, creatinine [25] | Alanine aminotransferase [53]; white blood cells count [25] | Total proteins [53]; vitamin D levels [87] |
| Cognition (poor) | [51, 65, 66, 88] | [48, 83, 85] | [22] |
| Metastasis location | Liver [51]; skeletal [24] | Bone [77, 78]; brain [78]; spinal [81] | Bone [22]; lung [81] |
| Psychological distress | [29, 88]; Mood (local questionnaire sad/depressed) [77]; depression (HAD) [22] | EORTC functioning [65, 66]; emotional non-well-being (FACT-G) or anxiety (MHI) [56]; anxiety (preop STAI) or Depression levels (preop BDI) [30] | EORTC functioning [51] |
| Sleep disturbance | [77] | [50, 51] | [22] |
| Pain related | |||
| Breakthrough cancer pain (presence vs absence) | [22] | [51, 59] | |
| Incidental (presence vs absence) | [50, 88] | [65, 66] | |
| Intensity | Self-reported δ VAS [58] | Baseline-intervals [50]; initial pain intensity [83] | Initial worst pain severity [56] |
| Pathophysiology (neuropathic pain) | [35, 38, 43, 51, 58, 78] | Presence vs absence [24, 88]; neuropathic versus nociceptive [65, 66] | Presence vs absence [22] |
| Drug use | |||
| Analgesics | [72]; NSAIDs [50]; previous [24] | Ketorolac [62]; NSAIDs [78] | |
| Adjuvants | [35]; Anticonvulsants [22]; gabapentin [51]; antidepressants (vs no antidepressant) [78] | Steroids or non-opioids [51]; steroids [78]; traditional sedatives [81] | |
| Others | Oncologic treatments [24]; neuromuscular blockade [62] | Antiemetics and beta blockers [25] | PPIs and recent chemotherapy (14 days) [25]; Prophylactic laxative treatments [63] |
BDI Beck Depression Inventory, EORTC European Organization for Research and Treatment of Cancer, FACT-G Functional Assessment of Cancer Therapy-General, HAD Hospital Anxiety and Depression, MHI Mental Health Inventory, MMSE Mini Mental State Examination, NSAID Non-Steroidal Anti-Inflammatory Drug, PPI Proton-pump Inhibitor, STAI State-Trait Anxiety Inventory, VAS Visual Analog Scale