***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Abstract We studied the prevalence of chronic pain and long term sensory changes after cosmetic augmentation mammoplasty and the effects of a single i.v . preoperative dose of methylprednisolone 125 mg ( n = 74 ) , parecoxib 40 mg ( n = 71 ) , or placebo  ( n = 74 ) . A question naire was mailed 6 weeks and 1 year after surgery . Response rate after 1 year was 80 % . At 1 year non‐evoked pain was present in 13 % , and evoked pain was present in 20 % with no statistically significant differences between the groups . Methylprednisolone was associated with reduced odds for hyperesthesia at 1 year ( OR 0.3 , 95 % CI 0.1–0.6 ) , and significantly reduced the prevalence of hyperesthesia ( 30 % ) compared with placebo ( 56 % , P < 0.01 ) and parecoxib ( 51 % , P < 0.04 ) . Factors associated with increased odds for pain at 1 year were intensity of pain during the first 6 days after surgery ( OR 1.3 , 95 % CI 1.1–1.6 ) , pain at 6 weeks ( OR 18.4 , 95 % CI 6.9–49.3 ) , hyperesthesia at 6 weeks ( OR 2.3 , 95 % CI 1.1–5.1 ) and present hyperesthesia ( OR 3.1 , 95 % CI 1.4–6.7 ) . We conclude that persistent pain and sensory changes are common after augmentation mammoplasty , and that patients having pain at 6 weeks most likely will have pain also at 1 year . Acute postoperative pain , hyperesthesia at 6 weeks , and the presence of hyperesthesia increased the odds for pain at 1 year . Preoperative methylprednisolone result ed in significantly less hyperesthesia compared with both parecoxib and placebo , but did not significantly reduce the prevalence of persistent spontaneous or evoked pain Background : Sympathetic blockade with local anesthetics is used frequently in the management of  complex regional pain syndrome type 1(CRPS-1 ) , with variable degrees of success in pain relief . The current study investigated which signs or symptoms of CRPS-1 could be predictive of outcome . The incidence of side effects and complications of sympathetic blockade also were determined prospect ively . Methods : A prospect i ve observational study was done of 49 patients with CRPS-1 in one extremity only and for less than 1-yr duration who had severe pain and persistent functional impairment with no response to st and ard treatment with medication and physical therapy .  Results : Fifteen ( 31 % ) patients had good or moderate response . The response rate was not different in patient groups with cold or warm type CRPS-1 or in those with more or less than 1.5 ° C differential increase in skin temperature after sympathetic blockade . Allodynia and hypoesthesia were negative predictors for treatment success in CRPS-1 . There were no symptoms or signs of CRPS-1 that positively predicted treatment success . A majority of patients ( 84 % ) experienced transient side effects such as headache , dysphagia , increased pain , backache , nausea , blurred vision , groin pain , hoarseness , and hematoma at the puncture site . No major complications were reported . Conclusions : The presence of allodynia and hypoesthesia are negative predictors for treatment success . The selection of sympathetic blockade as treatment for CRPS-1 should be balanced carefully between potential success and side effect ratio . The procedure is as likely to cause a transient increase in pain as a decrease in pain . Patients should be informed accordingly BACKGROUND Spinal cord stimulation ( SCS ) has proven to be an effective however an invasive and relatively expensive treatment of chronic Complex Regional Pain Syndrome type 1(CRPS-1 ) . Furthermore , in one third of CRPS-1 patients , SCS treatment fails to give significant pain relief and 32 - 38 % of treated patients experience complications . The aim of the current study was to develop effective prognostic factors for prediction of successful outcome of SCS . METHODS AND RESULTS The study population consisted of 36 chronic CRPS patients enrolled in a r and omized controlled trial of SCS efficacy . We analyzed various prognostic factors in the group of patients treated with SCS and compared baseline values of possible predictors of outcome in the successfully treated and the not successfully treated group . Success was defined as Patient Global Perceived Impression of Change score of at least " much improved " and pain reduction of at least 2.5 on a visual-analogue scale ( VAS score 0 - 10 ) . Univariate analyses showed that patient age , duration of the disease , localization of the disease , intensity of the pain , and the presence of mechanical hypoesthesia did not predict SCS success . The mean and maximum value of brush-evoked allodynia proved to be statistically significant predictors of outcome . Using Receiver-Operating Characteristic ( ROC ) curve analyses of maximum allodynia values , the diagnostic sensitivity for successful SCS was 0.75 and the specificity 0.81 . CONCLUSION Brush-evoked allodynia may be a significant negative prognostic factor of SCS treatment outcome after 1 year in chronic CRPS-1 Background Herpes zoster ( HZ ) is a common disease , characterized by rash-associated localized pain . Its main complication , post-herpetic neuralgia ( PHN ) , is difficult to treat and may last for months to years in the wake of rash resolution . Uncertainties remain as to the knowledge of predictors of HZ-related pain , including the role of antiviral therapy in preventing PHN in ordinary clinical practice . This prospect i ve cohort study was aim ed at investigating pain intensity at HZ presentation and its correlates , as well as the incidence of PHN and its predictors . Methods Patients diagnosed with HZ were consecutively enrolled by a network of Italian General Practitioners and Hospital Units in the health district of Pescara , Italy , over two years . Uncertain cases were referred for microbiological investigation . Data were collected through electronic case report form ( e-CRFs ) at enrolment and at 1 , 3 , 6 and 12 months after enrolment . Pain intensity was coded on a five-degree semi-quantitative scale at each time point . PHN was defined as pain of any intensity during follow-up and quantified using an area-under-the-curve ( AUC ) method . Results Four hundred and forty-one patients composed the final sample . Mean age was 58.1 years ( SD = 20.4 years ) ; 43.5 % of patients were males ; 7.9 % did not receive prescription of antivirals .  Intense/very intense pain at presentation was reported by 25.2 % of patients and was significantly associated with female gender , older age , cigarette smoking , trauma and /or surgery at HZ site ( logistic regression ) . PHN was diagnosed in 51.2 % of patients at one month and in 30.0 % of patients at three months . PHN was significantly associated with pain intensity at presentation , age , smoking , trauma and missed antiviral prescription ( generalized estimating equations model ) . The same factors were also independent predictors of the overall pain burden as described by the AUC method ( linear regression ) . Conclusions Smoking , traumas and surgery at the HZ site emerged as new predictors of both HZ-related pain intensity and persistence , opening new perspectives in the prevention of HZ-related pain . An independent line of evidence was provided for the efficacy of antiviral therapy in preventing PHN and reducing total pain burden Summary Despite early diagnosis and treatment with antiviral agents , many herpes zoster patients report persistent  pain and marked long‐term reduction in health‐related quality of life . Abstract Underst and ing the effect of herpes zoster and zoster‐related pain should inform care to improve health‐related quality of life in elderly patients . A 12‐month , longitudinal , prospect i ve , multicenter observational study conducted in primary care in France enrolled patients aged ⩾50 years with acute eruptive herpes zoster . Patient‐reported zoster‐related pain was assessed by vali date d question naires ( Douleur Neuropathique en 4 Questions [ DN4 ] , Zoster Brief Pain Inventory [ ZBPI ] , and Neuropathic Pain Symptom Inventory [ NPSI ] ) on days 0 and 15 , and at months 1 , 3 , 6 , 9 , and 12 . Health‐related quality of life was assessed by the 12‐item short‐form health survey ( SF‐12 ) and the Hospital Anxiety and Depression scale on day 0 and at months 3 , 6 , and 12 . Of 1358 patients included , 1032 completed follow‐up . Mean ± st and ard deviation age was 67.7 ± 10.7 ( range , 50–95 ) years ; 62.2 % were women . Most patients ( 94.1 % ) were prescribed antiviral drugs . The prevalence of zoster‐related pain on day 0 and at months 3 , 6 , 9 , and 12 was 79.6 % , 11.6 % , 8.5 % , 7.4 % , and 6.0 % , respectively . Patients with persistent pain had lower scores on the physical and mental component summaries of the SF‐12 and the ZBPI interference score than those without pain . By logistic regression analysis , main predictive factors on day 0 for postherpetic neuralgia at month 3 were age , male sex , ZBPI interference score , Physical Component Summary score of the SF‐12 , and neuropathic quality of pain ( DN4 score ⩾4 ) . Despite early diagnosis and treatment with antiviral agents , many patients with herpes zoster experience persistent pain and marked long‐term reduction in health‐related quality of life Background : Women scheduled to undergo hysterectomy for benign indications frequently have preoperative pelvic pain , but it is largely unknown why pain in some cases persists or even develops after surgery . This nationwide question naire and data base study describes pain and identifies risk factors for chronic  postsurgical pain  1 yr after hysterectomy for benign indications . Methods : A pain question naire was mailed to 1,299 women 1 yr after hysterectomy .  The response rate was 90.3 % , and the presence of persistent pain was correlated to indication for surgery , surgical procedure , type of anesthesia , and other perioperative data . Results : Pain was reported by 31.9 % 1 yr after hysterectomy ( chronic pain ) , and 13.7 % had pain more than 2 days a week . Pain was not present before surgery in 14.9 % of women with chronic postsurgical pain . Risk factors for chronic pain were preoperative pelvic pain ( odds ratio [ OR ] , 3.25 ; 95 % confidence interval [ CI ] , 2.40–4.41 ) , previous cesarean delivery ( OR , 1.54 ; CI , 1.06–2.26 ) , pain as the main indication for surgery ( OR , 2.98 ; CI , 1.54–5.77 ) , and pain problems elsewhere ( OR , 3.19 ; CI , 2.29–4.44 ) . Vaginal hysterectomy versus total abdominal hysterectomy was not significantly associated with a lower risk of chronic pain ( OR , 0.70 ; CI , 0.46–1.06 ) . Importantly , spinal versus general anesthesia was associated with less chronic pain ( OR , 0.42 ; CI , 0.21–0.85 ) . Conclusions : Thirty-two percent had chronic pain after hysterectomy , and risk factors were comparable to those seen in other operations . Interestingly , spinal anesthesia was associated with a lower frequency of chronic pain , justifying prospect i ve study of spinal anesthesia for patients with a high risk for development of chronic postsurgical pain Objectives : To identify risk factors for postherpetic neuralgia ( PHN ) using a vali date d definition of this chronic neuropathic pain syndrome , to determine combinations of risk factors that identify patients with a high risk of developing PHN , and to examine the characteristics of patients with subacute herpetic neuralgia , that is , pain that persists beyond the acute phase of herpes zoster but that resolves before PHN can be diagnosed . Methods : The authors examined baseline and follow-up data from 965 herpes zoster patients enrolled within 72 hours of rash onset in two clinical trials of famciclovir .  Results : Univariate and multivariate analyses indicated that older age , female sex , presence of a prodrome , greater rash severity , and greater acute pain severity made independent contributions to identifying which patients developed PHN . Patients with subacute herpetic neuralgia who did not develop PHN were significantly younger and had less severe acute pain than PHN patients but were significantly more likely to have severe and widespread rash than patients without persisting pain . Conclusions : The independent contributions to the prediction of PHN made by older age , female sex , presence of a prodrome , greater rash severity , and greater acute pain severity suggest that these risk factors reflect different mechanisms that each contribute to the development of PHN . Subacute herpetic neuralgia that does not progress to PHN may reflect peripheral tissue damage and inflammation caused by a particularly severe or widespread rash Seventy-one patients presenting with acute herpes zoster ophthalmicus were followed up for six months for a prospect i ve analysis of the natural history of the disease . Acute and chronic ocular complications , nasociliary nerve involvement , age , sex , rash , and pain were assessed , and the results are presented . Acute pain was measured by a visual analogue scale . Postherpetic neuralgia ( PHN ) was more likely in patients over 80 and in those who scored their pain highly at presentation . Duration of rash was longer in patients who developed PHN 
    Output:
    
High- quality studies mainly assessed factors related to disease functions and structures .