setTimeout not working as desired?

I am using socket.io to send some data continuously from server to client. So i was using the setTimeout function to send the data periodically. And the sleep time is not constant so am not using setInterval. But setTimeout is not working. I am using service bus to get some data from my worker role which am forwarding to the client at regular intervals. Here is my code.

var sleepTime;

function requestQueue() {

sleepTime = 0;

console.log("REQUEST QUEUE STARTED");

console.log("SEND to WORKER ROLE");
// send the request to worker role
var broadcastMessage = {}
broadcastMessage.Channel = "World";
broadcastMessage.BufferSize = 10;     

sendMessage(socketToWorkerRole, broadcastMessage)

receivePeriodicRecordsQueue(workerRoleToSocket);
}

////

function receivePeriodicRecordsQueue(queue) {

serviceBusService.receiveQueueMessage(queue, function (error, receivedMessage) {
    if (!error) {
        if (receivedMessage != null) {
            var messageBody = receivedMessage.body;

            if (messageBody != null) {

                // Lots of processing and calculating sleep time

                    // SET TIMEOUT
                    if (sleepTime != 0) {
                        console.log("SLEEP TIME:" + sleepTime);
                        setTimeout(function () { requestQueue(); }, sleepTime);
                    }

                      // sending data to client through socket
                    io.sockets.emit('broadcast', recordsQueue);

                }

            }
        }
    }
    else {
        console.log(error);
    }
})

}

Am basically a C# programmer, very new to JS. Please let me know if my implementation of setTimeout is wrong. Essentially i want the requestQueue method to be called periodically using a variable sleep time

EDIT ANSWER:

In my case it was a silly issue. I was using the sleep time in seconds instead of milliseconds. setTimeout requires milliseconds. But i have marked scott's as the answer because i thought the async module is pretty useful and can be used as a replacement for setTimeout and for a lot of other functionalities if needed.