/**
* Top Drugs by Adverse Events Resource
* Real-time analysis showing top 10 drugs with most adverse events reported in the last 30 days
*/
import { BaseResource, ResourceContent } from './base.js';
import { logger } from '../logging/index.js';
export class TopDrugsByAdverseEventsResource extends BaseResource {
constructor() {
super(
'fda://safety/top-drugs-aes',
'Top Drugs by Adverse Events',
'Top 10 drugs with the most adverse events reported in the last 30 days from FAERS database',
'application/json'
);
}
private calculateDateRange(): { startDate: string; endDate: string } {
const today = new Date();
const thirtyDaysAgo = new Date();
thirtyDaysAgo.setDate(today.getDate() - 30);
// Format as YYYYMMDD for FDA API
const formatDate = (date: Date): string => {
return date.getFullYear().toString() +
(date.getMonth() + 1).toString().padStart(2, '0') +
date.getDate().toString().padStart(2, '0');
};
return {
startDate: formatDate(thirtyDaysAgo),
endDate: formatDate(today)
};
}
private async fetchTopDrugsByAdverseEvents(): Promise<any> {
let { startDate, endDate } = this.calculateDateRange();
// Use count parameter to get top drugs by adverse event count
// URL encode the brackets for proper API formatting
const encodedDateRange = `receivedate:%5B${startDate}+TO+${endDate}%5D`;
let fdaUrl = `https://api.fda.gov/drug/event.json?search=${encodedDateRange}&count=patient.drug.medicinalproduct.exact&limit=10`;
let response = await fetch(fdaUrl);
// If no data for last 30 days, try last 90 days as fallback
if (!response.ok || response.status === 404) {
const ninetyDaysAgo = new Date();
ninetyDaysAgo.setDate(ninetyDaysAgo.getDate() - 90);
const fallbackStartDate = this.formatDate(ninetyDaysAgo);
const fallbackDateRange = `receivedate:%5B${fallbackStartDate}+TO+${endDate}%5D`;
fdaUrl = `https://api.fda.gov/drug/event.json?search=${fallbackDateRange}&count=patient.drug.medicinalproduct.exact&limit=10`;
response = await fetch(fdaUrl);
}
// If still no data, try last year as final fallback
if (!response.ok || response.status === 404) {
const oneYearAgo = new Date();
oneYearAgo.setFullYear(oneYearAgo.getFullYear() - 1);
const yearStartDate = this.formatDate(oneYearAgo);
const yearDateRange = `receivedate:%5B${yearStartDate}+TO+${endDate}%5D`;
fdaUrl = `https://api.fda.gov/drug/event.json?search=${yearDateRange}&count=patient.drug.medicinalproduct.exact&limit=10`;
response = await fetch(fdaUrl);
}
if (!response.ok) {
throw new Error(`FDA API error: ${response.status} - ${response.statusText}`);
}
const data = await response.json();
// Check if we got actual results
if (data.error || !data.results || data.results.length === 0) {
throw new Error('No adverse events data found in the specified time period');
}
return data;
}
private formatDate(date: Date): string {
return date.getFullYear().toString() +
(date.getMonth() + 1).toString().padStart(2, '0') +
date.getDate().toString().padStart(2, '0');
}
private async fetchSeriousEventsBreakdown(topDrugs: string[]): Promise<any[]> {
const { startDate, endDate } = this.calculateDateRange();
const seriousEventsData = [];
// Get serious events data for top 5 drugs
for (const drug of topDrugs.slice(0, 5)) {
try {
const encodedDrug = encodeURIComponent(drug);
const encodedDateRange = `receivedate:%5B${startDate}+TO+${endDate}%5D`;
const seriousUrl = `https://api.fda.gov/drug/event.json?search=patient.drug.medicinalproduct:"${encodedDrug}"+AND+serious:1+AND+${encodedDateRange}&count=patient.reaction.reactionmeddrapt.exact&limit=5`;
const response = await fetch(seriousUrl);
if (response.ok) {
const data = await response.json();
if (data.results && data.results.length > 0) {
seriousEventsData.push({
drug: drug,
topReactions: data.results || []
});
}
}
} catch (error) {
logger.warn(`Failed to fetch serious events for drug: ${drug}`, {
error: (error as Error).message
}, {
component: 'TOP_DRUGS_AES_RESOURCE'
});
}
}
return seriousEventsData;
}
async getContent(): Promise<ResourceContent> {
const requestId = `trending-aes-${Date.now()}`;
try {
logger.info('Fetching top drugs by adverse events', {
component: 'TOP_DRUGS_AES_RESOURCE',
requestId
});
// Fetch top drugs with most adverse events
const topDrugsData = await this.fetchTopDrugsByAdverseEvents();
const topDrugs = topDrugsData?.results || [];
// Extract drug names for serious events analysis
const drugNames = topDrugs.map((result: any) => result.term);
// Fetch serious events breakdown for top drugs
const seriousEventsData = await this.fetchSeriousEventsBreakdown(drugNames);
// Calculate total adverse events across all top drugs
const totalEvents = topDrugs.reduce((sum: number, drug: any) => sum + drug.count, 0);
// Generate analysis period info
const { startDate, endDate } = this.calculateDateRange();
const analysisWindow = `${startDate.slice(0,4)}-${startDate.slice(4,6)}-${startDate.slice(6,8)} to ${endDate.slice(0,4)}-${endDate.slice(4,6)}-${endDate.slice(6,8)}`;
const trendingAnalysis = {
reportGenerated: new Date().toISOString(),
analysisWindow: analysisWindow,
analysisPeriod: "Last 30 days",
dataSource: "FDA Adverse Event Reporting System (FAERS)",
summary: {
totalTopDrugs: topDrugs.length,
totalAdverseEvents: totalEvents,
averageEventsPerDrug: topDrugs.length > 0 ? Math.round(totalEvents / topDrugs.length) : 0,
dataFreshness: "Real-time from FAERS database"
},
topDrugsByAdverseEvents: topDrugs.map((drug: any, index: number) => ({
rank: index + 1,
drugName: drug.term,
adverseEventCount: drug.count,
percentageOfTotal: topDrugs.length > 0 ? ((drug.count / totalEvents) * 100).toFixed(1) : "0.0"
})),
seriousEventsAnalysis: seriousEventsData.map(drugData => ({
drugName: drugData.drug,
topSeriousReactions: drugData.topReactions.slice(0, 3).map((reaction: any) => ({
reaction: reaction.term,
count: reaction.count
}))
})),
trendingInsights: this.generateTrendingInsights(topDrugs, totalEvents),
methodology: {
dataSource: "FDA FAERS (Adverse Event Reporting System)",
countMethod: "Aggregated by drug name using FDA count API",
timeWindow: "Rolling 30-day window",
includedEvents: "All adverse events (serious and non-serious)",
limitations: [
"Voluntary reporting system - underreporting expected",
"Counts reflect reporting volume, not incidence rates",
"Multiple reports for same patient/event possible",
"Drug name variations may affect aggregation"
]
},
metadata: {
queryDate: new Date().toISOString(),
fdaApiEndpoint: "drug/event.json with count parameter",
processingNote: "Data includes all medicinal products reported in adverse events",
updateFrequency: "Real-time (updated when resource is accessed)"
}
};
return {
uri: this.resourceUri,
mimeType: this.mimeType,
text: JSON.stringify(trendingAnalysis, null, 2),
metadata: {
generatedAt: new Date().toISOString(),
dataFreshness: 'real-time',
contentSize: JSON.stringify(trendingAnalysis).length,
analysisWindow: analysisWindow,
totalDrugsAnalyzed: topDrugs.length
}
};
} catch (error) {
logger.error('Failed to fetch top drugs by adverse events data', error as Error, {
component: 'TOP_DRUGS_AES_RESOURCE',
requestId
});
const errorResponse = {
error: 'Failed to retrieve top drugs by adverse events data',
message: (error as Error).message,
timestamp: new Date().toISOString(),
fallbackRecommendation: 'Check FDA FAERS database directly or try again later',
dataSource: "FDA Adverse Event Reporting System (FAERS)",
analysisWindow: "Last 30 days"
};
return {
uri: this.resourceUri,
mimeType: this.mimeType,
text: JSON.stringify(errorResponse, null, 2),
metadata: {
generatedAt: new Date().toISOString(),
dataFreshness: 'error',
contentSize: JSON.stringify(errorResponse).length
}
};
}
}
private generateTrendingInsights(topDrugs: any[], totalEvents: number): string[] {
const insights = [];
if (topDrugs.length > 0) {
const topDrug = topDrugs[0];
const topDrugPercentage = ((topDrug.count / totalEvents) * 100).toFixed(1);
insights.push(`${topDrug.term} leads with ${topDrug.count} adverse events (${topDrugPercentage}% of top 10 total)`);
}
if (topDrugs.length >= 3) {
const top3Total = topDrugs.slice(0, 3).reduce((sum: number, drug: any) => sum + drug.count, 0);
const top3Percentage = ((top3Total / totalEvents) * 100).toFixed(1);
insights.push(`Top 3 drugs account for ${top3Percentage}% of adverse events in the analysis period`);
}
if (topDrugs.length >= 5) {
const variationCoeff = this.calculateVariationCoefficient(topDrugs.slice(0, 5));
if (variationCoeff > 0.5) {
insights.push("High variation in reporting volume suggests diverse drug usage patterns");
} else {
insights.push("Consistent reporting volume across top drugs indicates stable usage patterns");
}
}
insights.push(`Analysis based on ${totalEvents} total adverse events from FAERS database`);
return insights;
}
private calculateVariationCoefficient(drugs: any[]): number {
const counts = drugs.map(drug => drug.count);
const mean = counts.reduce((sum, count) => sum + count, 0) / counts.length;
const variance = counts.reduce((sum, count) => sum + Math.pow(count - mean, 2), 0) / counts.length;
const stdDev = Math.sqrt(variance);
return stdDev / mean;
}
}
